A027242 a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026769.

1, 10, 68, 402, 2258, 12072, 64963, 338824, 1817063, 9467940, 51258781, 269085042, 1475551064, 7822940886, 43422818989, 232480179882, 1303561020575, 7040175844640, 39786449049369, 216469879238194, 1230485470688864, 6736096483008440, 38451562317699992, 211571284685596944

Offset: 3

Author

Clark Kimberling

Keywords

• nonn

Extensions

More terms from Sean A. Irvine, Oct 26 2019