Column 4 of triangle A113983; also a(n) = A113983(n+3,3) + [A113983^2](n+2,3).
A113987
Column 4 of triangle A113983; also a(n) = A113983(n+3,3) + [A113983^2](n+2,3).
Terms
- a(0) =1a(1) =5a(2) =21a(3) =89a(4) =401a(5) =1969a(6) =10633a(7) =63297a(8) =414857a(9) =2984829a(10) =23485909a(11) =201272257a(12) =1870901681a(13) =18786935025a(14) =203013976769
External references
- oeis: A113987