Av(1342, 1423, 1432, 3214)
Generating Function
\(\displaystyle \frac{\left(x^{2}+x -1\right) \left(x -1\right)^{2}}{x^{6}+2 x^{5}+4 x^{4}+x^{3}-4 x^{2}+4 x -1}\)
Counting Sequence
1, 1, 2, 6, 20, 64, 193, 565, 1646, 4819, 14177, 41788, 123170, 362838, 1068452, ...
Implicit Equation for the Generating Function
\(\displaystyle \left(x^{6}+2 x^{5}+4 x^{4}+x^{3}-4 x^{2}+4 x -1\right) F \! \left(x \right)-\left(x^{2}+x -1\right) \left(x -1\right)^{2} = 0\)
Recurrence
\(\displaystyle a \! \left(0\right) = 1\)
\(\displaystyle a \! \left(1\right) = 1\)
\(\displaystyle a \! \left(2\right) = 2\)
\(\displaystyle a \! \left(3\right) = 6\)
\(\displaystyle a \! \left(4\right) = 20\)
\(\displaystyle a \! \left(5\right) = 64\)
\(\displaystyle a \! \left(n +6\right) = a \! \left(n \right)+2 a \! \left(n +1\right)+4 a \! \left(n +2\right)+a \! \left(n +3\right)-4 a \! \left(n +4\right)+4 a \! \left(n +5\right), \quad n \geq 6\)
\(\displaystyle a \! \left(1\right) = 1\)
\(\displaystyle a \! \left(2\right) = 2\)
\(\displaystyle a \! \left(3\right) = 6\)
\(\displaystyle a \! \left(4\right) = 20\)
\(\displaystyle a \! \left(5\right) = 64\)
\(\displaystyle a \! \left(n +6\right) = a \! \left(n \right)+2 a \! \left(n +1\right)+4 a \! \left(n +2\right)+a \! \left(n +3\right)-4 a \! \left(n +4\right)+4 a \! \left(n +5\right), \quad n \geq 6\)
Explicit Closed Form
\(\displaystyle -\frac{11423 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =1\right)^{-n +4}}{24254501}-\frac{11423 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =2\right)^{-n +4}}{24254501}-\frac{11423 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =3\right)^{-n +4}}{24254501}-\frac{11423 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =4\right)^{-n +4}}{24254501}-\frac{11423 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =5\right)^{-n +4}}{24254501}-\frac{11423 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =6\right)^{-n +4}}{24254501}+\frac{113561 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =1\right)^{-n +3}}{24254501}+\frac{113561 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =2\right)^{-n +3}}{24254501}+\frac{113561 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =3\right)^{-n +3}}{24254501}+\frac{113561 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =4\right)^{-n +3}}{24254501}+\frac{113561 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =5\right)^{-n +3}}{24254501}+\frac{113561 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =6\right)^{-n +3}}{24254501}-\frac{282792 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =1\right)^{-n +2}}{24254501}-\frac{282792 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =2\right)^{-n +2}}{24254501}-\frac{282792 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =3\right)^{-n +2}}{24254501}-\frac{282792 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =4\right)^{-n +2}}{24254501}-\frac{282792 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =5\right)^{-n +2}}{24254501}-\frac{282792 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =6\right)^{-n +2}}{24254501}+\frac{305838 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =1\right)^{-n +1}}{24254501}+\frac{305838 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =2\right)^{-n +1}}{24254501}+\frac{305838 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =3\right)^{-n +1}}{24254501}+\frac{305838 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =4\right)^{-n +1}}{24254501}+\frac{305838 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =5\right)^{-n +1}}{24254501}+\frac{305838 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =6\right)^{-n +1}}{24254501}+\frac{1416856 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =1\right)^{-n -1}}{24254501}+\frac{1416856 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =2\right)^{-n -1}}{24254501}+\frac{1416856 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =3\right)^{-n -1}}{24254501}+\frac{1416856 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =4\right)^{-n -1}}{24254501}+\frac{1416856 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =5\right)^{-n -1}}{24254501}+\frac{1416856 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =6\right)^{-n -1}}{24254501}+\frac{2780446 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =1\right)^{-n}}{24254501}+\frac{2780446 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =2\right)^{-n}}{24254501}+\frac{2780446 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =3\right)^{-n}}{24254501}+\frac{2780446 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =4\right)^{-n}}{24254501}+\frac{2780446 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =5\right)^{-n}}{24254501}+\frac{2780446 \mathit{RootOf} \left(Z^{6}+2 Z^{5}+4 Z^{4}+Z^{3}-4 Z^{2}+4 Z -1, \mathit{index} =6\right)^{-n}}{24254501}\)
This specification was found using the strategy pack "Point Placements" and has 68 rules.
Found on January 18, 2022.Finding the specification took 1 seconds.
Copy 68 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_{4}\! \left(x \right) F_{5}\! \left(x \right)\\
F_{4}\! \left(x \right) &= x\\
F_{5}\! \left(x \right) &= F_{13}\! \left(x \right)+F_{6}\! \left(x \right)\\
F_{6}\! \left(x \right) &= F_{1}\! \left(x \right)+F_{7}\! \left(x \right)\\
F_{7}\! \left(x \right) &= F_{8}\! \left(x \right)\\
F_{8}\! \left(x \right) &= F_{4}\! \left(x \right) F_{9}\! \left(x \right)\\
F_{9}\! \left(x \right) &= F_{10}\! \left(x \right)+F_{6}\! \left(x \right)\\
F_{10}\! \left(x \right) &= F_{11}\! \left(x \right)+F_{4}\! \left(x \right)\\
F_{11}\! \left(x \right) &= F_{12}\! \left(x \right)\\
F_{12}\! \left(x \right) &= F_{4}\! \left(x \right) F_{7}\! \left(x \right)\\
F_{13}\! \left(x \right) &= F_{14}\! \left(x \right)+F_{2}\! \left(x \right)\\
F_{14}\! \left(x \right) &= F_{15}\! \left(x \right)+F_{16}\! \left(x \right)+F_{54}\! \left(x \right)\\
F_{15}\! \left(x \right) &= 0\\
F_{16}\! \left(x \right) &= F_{17}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{17}\! \left(x \right) &= F_{18}\! \left(x \right)+F_{24}\! \left(x \right)\\
F_{18}\! \left(x \right) &= F_{19}\! \left(x \right)+F_{7}\! \left(x \right)\\
F_{19}\! \left(x \right) &= F_{15}\! \left(x \right)+F_{20}\! \left(x \right)+F_{22}\! \left(x \right)\\
F_{20}\! \left(x \right) &= F_{21}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{21}\! \left(x \right) &= F_{18}\! \left(x \right)\\
F_{22}\! \left(x \right) &= F_{23}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{23}\! \left(x \right) &= F_{10}\! \left(x \right)\\
F_{24}\! \left(x \right) &= F_{25}\! \left(x \right)+F_{34}\! \left(x \right)\\
F_{25}\! \left(x \right) &= F_{26}\! \left(x \right)\\
F_{26}\! \left(x \right) &= F_{27}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{27}\! \left(x \right) &= F_{28}\! \left(x \right)+F_{29}\! \left(x \right)\\
F_{28}\! \left(x \right) &= F_{2}\! \left(x \right)+F_{25}\! \left(x \right)\\
F_{29}\! \left(x \right) &= F_{30}\! \left(x \right)+F_{32}\! \left(x \right)\\
F_{30}\! \left(x \right) &= F_{31}\! \left(x \right)\\
F_{31}\! \left(x \right) &= F_{2}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{32}\! \left(x \right) &= F_{33}\! \left(x \right)\\
F_{33}\! \left(x \right) &= F_{25}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{34}\! \left(x \right) &= 2 F_{15}\! \left(x \right)+F_{35}\! \left(x \right)+F_{37}\! \left(x \right)\\
F_{35}\! \left(x \right) &= F_{36}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{36}\! \left(x \right) &= F_{24}\! \left(x \right)\\
F_{37}\! \left(x \right) &= F_{38}\! \left(x \right) F_{4}\! \left(x \right)\\
F_{38}\! \left(x \right) &= F_{39}\! \left(x \right)\\
F_{39}\! \left(x \right) &= F_{40}\! \left(x \right)+F_{53}\! \left(x \right)\\
F_{40}\! \left(x \right) &= F_{15}\! \left(x \right)+F_{31}\! \left(x \right)+F_{41}\! \left(x \right)\\
F_{41}\! \left(x \right) &= F_{4}\! \left(x \right) F_{42}\! \left(x \right)\\
F_{42}\! \left(x \right) &= F_{43}\! \left(x \right)+F_{48}\! \left(x \right)\\
F_{43}\! \left(x \right) &= F_{4}\! \left(x \right)+F_{44}\! \left(x \right)\\
F_{44}\! \left(x \right) &= F_{15}\! \left(x \right)+F_{45}\! \left(x \right)+F_{47}\! \left(x \right)\\
F_{45}\! \left(x \right) &= F_{4}\! \left(x \right) F_{46}\! \left(x \right)\\
F_{46}\! \left(x \right) &= F_{43}\! \left(x \right)\\
F_{47}\! \left(x \right) &= x^{2}\\
F_{48}\! \left(x \right) &= F_{30}\! \left(x \right)+F_{49}\! \left(x \right)\\
F_{49}\! \left(x \right) &= 2 F_{15}\! \left(x \right)+F_{50}\! \left(x \right)+F_{52}\! \left(x \right)\\
F_{50}\! \left(x \right) &= F_{4}\! \left(x \right) F_{51}\! \left(x \right)\\
F_{51}\! \left(x \right) &= F_{48}\! \left(x \right)\\
F_{52}\! \left(x \right) &= F_{4}\! \left(x \right) F_{40}\! \left(x \right)\\
F_{53}\! \left(x \right) &= F_{33}\! \left(x \right)\\
F_{54}\! \left(x \right) &= F_{4}\! \left(x \right) F_{55}\! \left(x \right)\\
F_{55}\! \left(x \right) &= F_{13}\! \left(x \right)+F_{56}\! \left(x \right)\\
F_{56}\! \left(x \right) &= F_{40}\! \left(x \right)+F_{57}\! \left(x \right)\\
F_{57}\! \left(x \right) &= 2 F_{15}\! \left(x \right)+F_{33}\! \left(x \right)+F_{58}\! \left(x \right)\\
F_{58}\! \left(x \right) &= F_{4}\! \left(x \right) F_{59}\! \left(x \right)\\
F_{59}\! \left(x \right) &= F_{60}\! \left(x \right)+F_{64}\! \left(x \right)\\
F_{60}\! \left(x \right) &= F_{11}\! \left(x \right)+F_{61}\! \left(x \right)\\
F_{61}\! \left(x \right) &= F_{62}\! \left(x \right)\\
F_{62}\! \left(x \right) &= F_{4}\! \left(x \right) F_{63}\! \left(x \right)\\
F_{63}\! \left(x \right) &= F_{60}\! \left(x \right)\\
F_{64}\! \left(x \right) &= F_{32}\! \left(x \right)+F_{65}\! \left(x \right)\\
F_{65}\! \left(x \right) &= F_{66}\! \left(x \right)\\
F_{66}\! \left(x \right) &= F_{4}\! \left(x \right) F_{67}\! \left(x \right)\\
F_{67}\! \left(x \right) &= F_{64}\! \left(x \right)\\
\end{align*}\)