Av(2143, 2413, 415263)
Generating Function
\(\displaystyle -\frac{x}{2}+\frac{3}{2}-\frac{\sqrt{x^{2}-6 x +1}}{2}\)
Counting Sequence
1, 1, 2, 6, 22, 90, 394, 1806, 8558, 41586, 206098, 1037718, 5293446, 27297738, 142078746, ...
Implicit Equation for the Generating Function
\(\displaystyle F \left(x
\right)^{2}+\left(x -3\right) F \! \left(x \right)+2 = 0\)
Recurrence
\(\displaystyle a \! \left(0\right) = 1\)
\(\displaystyle a \! \left(1\right) = 1\)
\(\displaystyle a \! \left(n +2\right) = -\frac{\left(n -1\right) a \! \left(n \right)}{n +2}+\frac{3 \left(2 n +1\right) a \! \left(n +1\right)}{n +2}, \quad n \geq 2\)
\(\displaystyle a \! \left(1\right) = 1\)
\(\displaystyle a \! \left(n +2\right) = -\frac{\left(n -1\right) a \! \left(n \right)}{n +2}+\frac{3 \left(2 n +1\right) a \! \left(n +1\right)}{n +2}, \quad n \geq 2\)
This specification was found using the strategy pack "Point Placements Tracked Fusion Expand Verified" and has 48 rules.
Found on February 03, 2022.Finding the specification took 969 seconds.
Copy 48 equations to clipboard:
\(\begin{align*}
F_{0}\! \left(x \right) &= F_{1}\! \left(x \right)+F_{2}\! \left(x \right)\\
F_{1}\! \left(x \right) &= 1\\
F_{2}\! \left(x \right) &= F_{3}\! \left(x \right)\\
F_{3}\! \left(x \right) &= F_{13}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{4}\! \left(x \right) &= F_{0}\! \left(x \right)+F_{5}\! \left(x \right)\\
F_{5}\! \left(x \right) &= F_{2}\! \left(x \right)+F_{6}\! \left(x \right)\\
F_{6}\! \left(x \right) &= F_{7}\! \left(x \right)\\
F_{7}\! \left(x \right) &= F_{13}\! \left(x \right) F_{8}\! \left(x \right)\\
F_{8}\! \left(x \right) &= F_{17}\! \left(x \right)+F_{9}\! \left(x \right)\\
F_{9}\! \left(x \right) &= F_{10}\! \left(x \right)\\
F_{10}\! \left(x \right) &= F_{11}\! \left(x \right) F_{13}\! \left(x \right) F_{14}\! \left(x \right)\\
F_{11}\! \left(x \right) &= \frac{F_{12}\! \left(x \right)}{F_{0}\! \left(x \right) F_{13}\! \left(x \right)}\\
F_{12}\! \left(x \right) &= F_{5}\! \left(x \right)\\
F_{13}\! \left(x \right) &= x\\
F_{14}\! \left(x \right) &= F_{0}\! \left(x \right)+F_{15}\! \left(x \right)\\
F_{15}\! \left(x \right) &= F_{16}\! \left(x \right)\\
F_{16}\! \left(x \right) &= F_{0}\! \left(x \right) F_{11}\! \left(x \right) F_{13}\! \left(x \right)\\
F_{17}\! \left(x \right) &= F_{18}\! \left(x , 1\right)\\
F_{18}\! \left(x , y\right) &= F_{19}\! \left(x , y\right)+F_{46}\! \left(x , y\right)\\
F_{19}\! \left(x , y\right) &= F_{20}\! \left(x , y\right)+F_{43}\! \left(x , y\right)\\
F_{20}\! \left(x , y\right) &= F_{21}\! \left(x , y\right)\\
F_{21}\! \left(x , y\right) &= F_{22}\! \left(x , y\right) F_{27}\! \left(x , y\right)\\
F_{22}\! \left(x , y\right) &= F_{23}\! \left(x , y\right)+F_{28}\! \left(x , y\right)\\
F_{23}\! \left(x , y\right) &= F_{0}\! \left(x \right) F_{24}\! \left(x , y\right)\\
F_{24}\! \left(x , y\right) &= F_{1}\! \left(x \right)+F_{25}\! \left(x , y\right)\\
F_{25}\! \left(x , y\right) &= F_{26}\! \left(x , y\right)\\
F_{26}\! \left(x , y\right) &= F_{24}\! \left(x , y\right) F_{27}\! \left(x , y\right)\\
F_{27}\! \left(x , y\right) &= y x\\
F_{28}\! \left(x , y\right) &= F_{29}\! \left(x , y\right)\\
F_{29}\! \left(x , y\right) &= F_{0}\! \left(x \right) F_{13}\! \left(x \right) F_{30}\! \left(x , y\right)\\
F_{31}\! \left(x , y\right) &= F_{27}\! \left(x , y\right) F_{30}\! \left(x , y\right)\\
F_{31}\! \left(x , y\right) &= F_{32}\! \left(x , y\right)\\
F_{32}\! \left(x , y\right) &= F_{19}\! \left(x , y\right)+F_{33}\! \left(x , y\right)\\
F_{33}\! \left(x , y\right) &= F_{34}\! \left(x , y\right)\\
F_{34}\! \left(x , y\right) &= F_{25}\! \left(x , y\right) F_{35}\! \left(x , y\right)\\
F_{36}\! \left(x , y\right) &= F_{24}\! \left(x , y\right) F_{35}\! \left(x , y\right)\\
F_{36}\! \left(x , y\right) &= F_{37}\! \left(x , y\right)\\
F_{38}\! \left(x , y\right) &= F_{37}\! \left(x , y\right)+F_{42}\! \left(x , y\right)\\
F_{39}\! \left(x , y\right) &= F_{13}\! \left(x \right) F_{38}\! \left(x , y\right)\\
F_{39}\! \left(x , y\right) &= F_{40}\! \left(x , y\right)\\
F_{41}\! \left(x , y\right) &= F_{24}\! \left(x , y\right)+F_{40}\! \left(x , y\right)\\
F_{41}\! \left(x , y\right) &= F_{0}\! \left(x \right)+F_{20}\! \left(x , y\right)\\
F_{42}\! \left(x , y\right) &= F_{19}\! \left(x , y\right)+F_{4}\! \left(x \right)\\
F_{43}\! \left(x , y\right) &= F_{44}\! \left(x , y\right)\\
F_{44}\! \left(x , y\right) &= F_{13}\! \left(x \right) F_{45}\! \left(x , y\right)\\
F_{45}\! \left(x , y\right) &= -\frac{y \left(F_{18}\! \left(x , 1\right)-F_{18}\! \left(x , y\right)\right)}{-1+y}\\
F_{46}\! \left(x , y\right) &= F_{47}\! \left(x , y\right)\\
F_{47}\! \left(x , y\right) &= F_{11}\! \left(x \right) F_{13}\! \left(x \right) F_{19}\! \left(x , y\right)\\
\end{align*}\)
This specification was found using the strategy pack "Insertion Point Placements Tracked Fusion" and has 141 rules.
Found on July 20, 2021.Finding the specification took 867 seconds.
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Copy 141 equations to clipboard:
\(\begin{align*}
F_{0}\! \left(x \right) &= F_{1}\! \left(x \right)+F_{2}\! \left(x \right)\\
F_{1}\! \left(x \right) &= 1\\
F_{2}\! \left(x \right) &= F_{3}\! \left(x \right)\\
F_{3}\! \left(x \right) &= F_{13}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{4}\! \left(x \right) &= F_{0}\! \left(x \right)+F_{5}\! \left(x \right)\\
F_{5}\! \left(x \right) &= F_{2}\! \left(x \right)+F_{6}\! \left(x \right)\\
F_{6}\! \left(x \right) &= F_{7}\! \left(x \right)\\
F_{7}\! \left(x \right) &= F_{13}\! \left(x \right) F_{8}\! \left(x \right)\\
F_{8}\! \left(x \right) &= F_{126}\! \left(x \right)+F_{9}\! \left(x \right)\\
F_{9}\! \left(x \right) &= F_{10}\! \left(x \right)+F_{122}\! \left(x \right)\\
F_{10}\! \left(x \right) &= F_{11}\! \left(x \right)+F_{15}\! \left(x \right)\\
F_{11}\! \left(x \right) &= F_{12}\! \left(x \right)\\
F_{12}\! \left(x \right) &= F_{13}\! \left(x \right) F_{14}\! \left(x \right)\\
F_{13}\! \left(x \right) &= x\\
F_{14}\! \left(x \right) &= F_{1}\! \left(x \right)+F_{11}\! \left(x \right)\\
F_{15}\! \left(x \right) &= F_{16}\! \left(x \right)+F_{2}\! \left(x \right)\\
F_{16}\! \left(x \right) &= F_{17}\! \left(x , 1\right)\\
F_{17}\! \left(x , y\right) &= F_{18}\! \left(x , y\right)\\
F_{18}\! \left(x , y\right) &= F_{19}\! \left(x , y\right) F_{24}\! \left(x , y\right)\\
F_{19}\! \left(x , y\right) &= F_{20}\! \left(x , y\right)+F_{25}\! \left(x , y\right)\\
F_{20}\! \left(x , y\right) &= F_{2}\! \left(x \right) F_{21}\! \left(x , y\right)\\
F_{21}\! \left(x , y\right) &= F_{1}\! \left(x \right)+F_{22}\! \left(x , y\right)\\
F_{22}\! \left(x , y\right) &= F_{23}\! \left(x , y\right)\\
F_{23}\! \left(x , y\right) &= F_{21}\! \left(x , y\right) F_{24}\! \left(x , y\right)\\
F_{24}\! \left(x , y\right) &= y x\\
F_{25}\! \left(x , y\right) &= F_{26}\! \left(x \right)+F_{29}\! \left(x , y\right)\\
F_{26}\! \left(x \right) &= -F_{0}\! \left(x \right)+F_{27}\! \left(x \right)\\
F_{27}\! \left(x \right) &= \frac{F_{28}\! \left(x \right)}{F_{13}\! \left(x \right)}\\
F_{28}\! \left(x \right) &= F_{2}\! \left(x \right)\\
F_{29}\! \left(x , y\right) &= F_{17}\! \left(x , y\right)+F_{30}\! \left(x , y\right)\\
F_{30}\! \left(x , y\right) &= F_{31}\! \left(x , y\right)\\
F_{31}\! \left(x , y\right) &= F_{13}\! \left(x \right) F_{32}\! \left(x , y\right)\\
F_{32}\! \left(x , y\right) &= F_{33}\! \left(x , y\right)+F_{43}\! \left(x , y\right)\\
F_{33}\! \left(x , y\right) &= F_{34}\! \left(x , y\right)+F_{41}\! \left(x , y\right)\\
F_{34}\! \left(x , y\right) &= F_{35}\! \left(x , y\right)+F_{38}\! \left(x , y\right)\\
F_{35}\! \left(x , y\right) &= F_{22}\! \left(x , y\right) F_{36}\! \left(x \right)\\
F_{36}\! \left(x \right) &= F_{2}\! \left(x \right)+F_{37}\! \left(x \right)\\
F_{37}\! \left(x \right) &= F_{0}\! \left(x \right) F_{2}\! \left(x \right)\\
F_{38}\! \left(x , y\right) &= F_{39}\! \left(x , y\right)+F_{40}\! \left(x , y\right)\\
F_{39}\! \left(x , y\right) &= F_{17}\! \left(x , y\right) F_{2}\! \left(x \right)\\
F_{40}\! \left(x , y\right) &= F_{0}\! \left(x \right) F_{30}\! \left(x , y\right)\\
F_{41}\! \left(x , y\right) &= F_{42}\! \left(x , y\right)\\
F_{42}\! \left(x , y\right) &= F_{0}\! \left(x \right) F_{2}\! \left(x \right) F_{21}\! \left(x , y\right) F_{22}\! \left(x , y\right)\\
F_{43}\! \left(x , y\right) &= F_{108}\! \left(x , y\right)+F_{44}\! \left(x , y\right)\\
F_{44}\! \left(x , y\right) &= F_{45}\! \left(x , y\right)+F_{47}\! \left(x , y\right)\\
F_{45}\! \left(x , y\right) &= F_{46}\! \left(x , y\right)\\
F_{46}\! \left(x , y\right) &= F_{2}\! \left(x \right) F_{22}\! \left(x , y\right) F_{36}\! \left(x \right)\\
F_{47}\! \left(x , y\right) &= F_{48}\! \left(x , y\right)+F_{99}\! \left(x , y\right)\\
F_{48}\! \left(x , y\right) &= F_{2}\! \left(x \right) F_{49}\! \left(x , y\right)\\
F_{49}\! \left(x , y\right) &= F_{50}\! \left(x , y\right)\\
F_{50}\! \left(x , y\right) &= F_{13}\! \left(x \right) F_{51}\! \left(x , y\right)\\
F_{51}\! \left(x , y\right) &= F_{52}\! \left(x , y\right)+F_{62}\! \left(x , y\right)\\
F_{52}\! \left(x , y\right) &= F_{53}\! \left(x , y\right)+F_{58}\! \left(x , y\right)\\
F_{53}\! \left(x , y\right) &= F_{54}\! \left(x , y\right)+F_{57}\! \left(x , y\right)\\
F_{54}\! \left(x , y\right) &= F_{55}\! \left(x , y\right)\\
F_{55}\! \left(x , y\right) &= F_{13}\! \left(x \right) F_{56}\! \left(x , y\right)\\
F_{56}\! \left(x , y\right) &= F_{22}\! \left(x , y\right)+F_{54}\! \left(x , y\right)\\
F_{57}\! \left(x , y\right) &= -\frac{y \left(F_{17}\! \left(x , 1\right)-F_{17}\! \left(x , y\right)\right)}{-1+y}\\
F_{58}\! \left(x , y\right) &= F_{59}\! \left(x , y\right)+F_{61}\! \left(x , y\right)\\
F_{59}\! \left(x , y\right) &= F_{60}\! \left(x , y\right)\\
F_{60}\! \left(x , y\right) &= F_{11}\! \left(x \right) F_{2}\! \left(x \right) F_{22}\! \left(x , y\right)\\
F_{61}\! \left(x , y\right) &= -\frac{y \left(F_{49}\! \left(x , 1\right)-F_{49}\! \left(x , y\right)\right)}{-1+y}\\
F_{62}\! \left(x , y\right) &= F_{63}\! \left(x , y\right)+F_{65}\! \left(x , y\right)\\
F_{63}\! \left(x , y\right) &= F_{64}\! \left(x , y\right)\\
F_{64}\! \left(x , y\right) &= F_{2}\! \left(x \right) F_{53}\! \left(x , y\right)\\
F_{65}\! \left(x , y\right) &= F_{66}\! \left(x , y\right)+F_{69}\! \left(x , y\right)\\
F_{66}\! \left(x , y\right) &= F_{67}\! \left(x , y\right)\\
F_{67}\! \left(x , y\right) &= F_{11}\! \left(x \right) F_{22}\! \left(x , y\right) F_{68}\! \left(x \right)\\
F_{68}\! \left(x \right) &= -F_{2}\! \left(x \right)+F_{26}\! \left(x \right)\\
F_{69}\! \left(x , y\right) &= -\frac{y \left(F_{70}\! \left(x , 1\right)-F_{70}\! \left(x , y\right)\right)}{-1+y}\\
F_{70}\! \left(x , y\right) &= F_{71}\! \left(x , y\right)\\
F_{71}\! \left(x , y\right) &= F_{13}\! \left(x \right) F_{72}\! \left(x , y\right)\\
F_{72}\! \left(x , y\right) &= F_{73}\! \left(x , y\right)+F_{80}\! \left(x , y\right)\\
F_{73}\! \left(x , y\right) &= F_{74}\! \left(x , y\right)+F_{77}\! \left(x , y\right)\\
F_{74}\! \left(x , y\right) &= F_{49}\! \left(x , y\right)+F_{75}\! \left(x , y\right)\\
F_{75}\! \left(x , y\right) &= F_{2}\! \left(x \right) F_{76}\! \left(x , y\right)\\
F_{76}\! \left(x , y\right) &= F_{17}\! \left(x , y\right)+F_{49}\! \left(x , y\right)\\
F_{77}\! \left(x , y\right) &= F_{78}\! \left(x , y\right)+F_{79}\! \left(x , y\right)\\
F_{78}\! \left(x , y\right) &= F_{2}\! \left(x \right) F_{49}\! \left(x , y\right)\\
F_{79}\! \left(x , y\right) &= F_{68}\! \left(x \right) F_{76}\! \left(x , y\right)\\
F_{80}\! \left(x , y\right) &= F_{81}\! \left(x , y\right)+F_{83}\! \left(x , y\right)\\
F_{81}\! \left(x , y\right) &= F_{82}\! \left(x , y\right)\\
F_{82}\! \left(x , y\right) &= F_{2}\! \left(x \right) F_{74}\! \left(x , y\right)\\
F_{83}\! \left(x , y\right) &= F_{84}\! \left(x , y\right)+F_{85}\! \left(x , y\right)\\
F_{84}\! \left(x , y\right) &= F_{49}\! \left(x , y\right) F_{6}\! \left(x \right)\\
F_{85}\! \left(x , y\right) &= F_{76}\! \left(x , y\right) F_{86}\! \left(x \right)\\
F_{86}\! \left(x \right) &= \frac{F_{87}\! \left(x \right)}{F_{0}\! \left(x \right)}\\
F_{87}\! \left(x \right) &= -F_{98}\! \left(x \right)+F_{88}\! \left(x \right)\\
F_{88}\! \left(x \right) &= -F_{96}\! \left(x \right)+F_{89}\! \left(x \right)\\
F_{89}\! \left(x \right) &= -F_{92}\! \left(x \right)+F_{90}\! \left(x \right)\\
F_{90}\! \left(x \right) &= \frac{F_{91}\! \left(x \right)}{F_{13}\! \left(x \right)}\\
F_{91}\! \left(x \right) &= F_{68}\! \left(x \right)\\
F_{92}\! \left(x \right) &= F_{36}\! \left(x \right)+F_{93}\! \left(x \right)\\
F_{93}\! \left(x \right) &= F_{94}\! \left(x \right)+F_{95}\! \left(x \right)\\
F_{94}\! \left(x \right) &= F_{2} \left(x \right)^{2}\\
F_{95}\! \left(x \right) &= F_{0}\! \left(x \right) F_{68}\! \left(x \right)\\
F_{96}\! \left(x \right) &= F_{97}\! \left(x \right)\\
F_{97}\! \left(x \right) &= F_{2}\! \left(x \right) F_{36}\! \left(x \right)\\
F_{98}\! \left(x \right) &= F_{2}\! \left(x \right) F_{6}\! \left(x \right)\\
F_{99}\! \left(x , y\right) &= F_{0}\! \left(x \right) F_{100}\! \left(x , y\right)\\
F_{101}\! \left(x , y\right) &= F_{100}\! \left(x , y\right)+F_{49}\! \left(x , y\right)\\
F_{102}\! \left(x , y\right) &= F_{101}\! \left(x , y\right)+F_{107}\! \left(x \right)\\
F_{103}\! \left(x , y\right) &= F_{102}\! \left(x , y\right)+F_{105}\! \left(x , y\right)\\
F_{104}\! \left(x , y\right) &= F_{103}\! \left(x , y\right) F_{24}\! \left(x , y\right)\\
F_{104}\! \left(x , y\right) &= F_{49}\! \left(x , y\right)\\
F_{105}\! \left(x , y\right) &= F_{106}\! \left(x , y\right)\\
F_{106}\! \left(x , y\right) &= F_{2} \left(x \right)^{2} F_{21}\! \left(x , y\right)\\
F_{107}\! \left(x \right) &= F_{6}\! \left(x \right)+F_{86}\! \left(x \right)\\
F_{108}\! \left(x , y\right) &= F_{109}\! \left(x , y\right)\\
F_{109}\! \left(x , y\right) &= F_{110}\! \left(x , y\right) F_{2}\! \left(x \right) F_{21}\! \left(x , y\right)\\
F_{111}\! \left(x , y\right) &= F_{110}\! \left(x , y\right) F_{21}\! \left(x , y\right)\\
F_{111}\! \left(x , y\right) &= F_{112}\! \left(x , y\right)\\
F_{113}\! \left(x , y\right) &= F_{112}\! \left(x , y\right)+F_{120}\! \left(x , y\right)\\
F_{114}\! \left(x , y\right) &= F_{113}\! \left(x , y\right)+F_{116}\! \left(x , y\right)\\
F_{115}\! \left(x , y\right) &= F_{114}\! \left(x , y\right) F_{13}\! \left(x \right)\\
F_{115}\! \left(x , y\right) &= F_{17}\! \left(x , y\right)\\
F_{116}\! \left(x , y\right) &= F_{117}\! \left(x , y\right)+F_{118}\! \left(x , y\right)\\
F_{117}\! \left(x , y\right) &= F_{17}\! \left(x , y\right)+F_{22}\! \left(x , y\right)\\
F_{118}\! \left(x , y\right) &= F_{119}\! \left(x , y\right)\\
F_{119}\! \left(x , y\right) &= F_{0}\! \left(x \right) F_{21}\! \left(x , y\right) F_{22}\! \left(x , y\right)\\
F_{120}\! \left(x , y\right) &= F_{121}\! \left(x , y\right)+F_{49}\! \left(x , y\right)\\
F_{121}\! \left(x , y\right) &= F_{2}\! \left(x \right) F_{22}\! \left(x , y\right)\\
F_{122}\! \left(x \right) &= F_{123}\! \left(x \right)+F_{124}\! \left(x \right)\\
F_{123}\! \left(x \right) &= F_{11}\! \left(x \right) F_{2}\! \left(x \right)\\
F_{124}\! \left(x \right) &= F_{125}\! \left(x \right)+F_{6}\! \left(x \right)\\
F_{125}\! \left(x \right) &= F_{49}\! \left(x , 1\right)\\
F_{126}\! \left(x \right) &= F_{127}\! \left(x \right)+F_{129}\! \left(x \right)\\
F_{127}\! \left(x \right) &= F_{128}\! \left(x \right)\\
F_{128}\! \left(x \right) &= F_{10}\! \left(x \right) F_{2}\! \left(x \right)\\
F_{129}\! \left(x \right) &= F_{130}\! \left(x \right)+F_{131}\! \left(x \right)\\
F_{130}\! \left(x \right) &= F_{11}\! \left(x \right) F_{68}\! \left(x \right)\\
F_{131}\! \left(x \right) &= F_{132}\! \left(x \right)+F_{140}\! \left(x \right)\\
F_{132}\! \left(x \right) &= F_{133}\! \left(x \right)\\
F_{133}\! \left(x \right) &= F_{13}\! \left(x \right) F_{134}\! \left(x \right)\\
F_{134}\! \left(x \right) &= F_{135}\! \left(x \right)+F_{138}\! \left(x \right)\\
F_{135}\! \left(x \right) &= F_{136}\! \left(x \right) F_{2}\! \left(x \right)\\
F_{136}\! \left(x \right) &= F_{107}\! \left(x \right)+F_{137}\! \left(x \right)\\
F_{137}\! \left(x \right) &= F_{37}\! \left(x \right)\\
F_{138}\! \left(x \right) &= F_{139}\! \left(x \right) F_{68}\! \left(x \right)\\
F_{139}\! \left(x \right) &= F_{136}\! \left(x \right)+F_{27}\! \left(x \right)\\
F_{140}\! \left(x \right) &= F_{70}\! \left(x , 1\right)\\
\end{align*}\)