A290445 a(n) = Bell(n-1)*Motzkin(n).

1, 2, 8, 45, 315, 2652, 25781, 283271, 3456900, 46269636, 672423050, 10525299270, 176275830495, 3141347954058, 59287984232184, 1180309480525515, 24699378929064513, 541636443419209128, 12413309505100590156, 296606717433660460083, 7373152497782026056948, 190310358028397003968473

Offset

1,2

Links

Table of n, a(n) for n=1..22.

Mathematica

motzkin[n_]:=Hypergeometric2F1[(1-n)/2, -n/2, 2, 4]; Table[BellB[n - 1] motzkin[n], {n, 50}] (* Indranil Ghosh, Aug 04 2017 *)

Crossrefs

Cf. A000110, A001006, A290444, A290446.

Sequence in context: A308599 A367316 A139678 * A152401 A325138 A358436

Adjacent sequences: A290442 A290443 A290444 * A290446 A290447 A290448

Keyword

nonn

Author

N. J. A. Sloane, Aug 04 2017

Status

approved