login
A226506
a(n) = B(n+2)-3*B(n+1)+B(n), where B(i) are the Bell numbers A000110.
2
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
0,3
LINKS
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.
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 *)
PROG
(Magma) [Bell(n+2)-3*Bell(n+1)+Bell(n): n in [0..30]]; // Vincenzo Librandi, Jul 16 2013
CROSSREFS
Cf. A000110.
Cf. A005493, A225591 (see Prop 3.1 (i) in Chern et al. link).
Sequence in context: A121177 A125831 A289787 * A026076 A361812 A231025
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jun 10 2013
STATUS
approved