A250106 Column 2 of triangle in A250104 (or A124323).

1, 0, 6, 10, 60, 231, 1148, 5832, 32175, 188375, 1169652, 7663734, 52808847, 381494400, 2881338840, 22696790440, 186058768140, 1584156272157, 13984151627030, 127779961705620, 1206805491491985, 11764472685724561, 118230099056654664

Offset: 2

Author

N. J. A. Sloane, Nov 16 2014

Keywords

• nonn

Links

• T. Mansour, A. O. Munagi, Set partitions with circular successions, European Journal of Combinatorics, 42 (2014), 207-216.

Crossrefs

Cf. A250104, A124323.

Programs

Maple

A250106 := proc(n)
    A124323(n,2) ;
end proc:
seq(A250106(n),n=2..50) ; # R. J. Mathar, Jan 22 2015

Mathematica

t[n_, k_] := Binomial[n, k] ((-1)^(n-k) + Sum[(-1)^(j-1) BellB[n-k-j], {j, 1, n-k}]);
Table[t[n, 2], {n, 2, 24}] (* Jean-François Alcover, Apr 03 2020 *)