A226506 a(n) = B(n+2)-3*B(n+1)+B(n), where B(i) are the Bell numbers A000110.

0, 0, 2, 12, 62, 320, 1712, 9604, 56674, 351792, 2293862, 15682216, 112179608, 837905016, 6522165834, 52807401908, 443962338894, 3869376656384, 34908008426360, 325530083655692, 3133830448212442, 31106728455899128, 318009567467999574, 3344865730200667832, 36161434396223563504

Offset: 0

Author

N. J. A. Sloane, Jun 10 2013

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..200
• B. Chern, P. Diaconis, D. M. Kane, and R. C. Rhoades, Closed expressions for averages of set partition statistics, arXiv:1304.4309 [math.CO], 2013.

Crossrefs

Cf. A000110.

Cf. A005493, A225591 (see Prop 3.1 (i) in Chern et al. link).

Programs

Magma

[Bell(n+2)-3*Bell(n+1)+Bell(n): n in [0..30]]; // Vincenzo Librandi, Jul 16 2013

Mathematica

Table[BellB[n+2] - 3 BellB[n+1] + BellB[n], {n, 0, 30}] (* Vincenzo Librandi, Jul 16 2013 *)
#[[3]]-3#[[2]]+#[[1]]&/@Partition[BellB[Range[0,30]],3,1] (* Harvey P. Dale, Aug 26 2021 *)