A250106 - OEIS

%I #17 Apr 03 2020 07:51:23

%S 1,0,6,10,60,231,1148,5832,32175,188375,1169652,7663734,52808847,

%T 381494400,2881338840,22696790440,186058768140,1584156272157,

%U 13984151627030,127779961705620,1206805491491985,11764472685724561,118230099056654664

%N Column 2 of triangle in A250104 (or A124323).

%H T. Mansour, A. O. Munagi, <a href="https://doi.org/10.1016/j.ejc.2014.06.008">Set partitions with circular successions</a>, European Journal of Combinatorics, 42 (2014), 207-216.

%p A250106 := proc(n)

%p     A124323(n,2) ;

%p end proc:

%p seq(A250106(n),n=2..50) ; # _R. J. Mathar_, Jan 22 2015

%t t[n_, k_] := Binomial[n, k] ((-1)^(n-k) + Sum[(-1)^(j-1) BellB[n-k-j], {j, 1, n-k}]);

%t Table[t[n, 2], {n, 2, 24}] (* _Jean-François Alcover_, Apr 03 2020 *)

%Y Cf. A250104, A124323.

%K nonn

%O 2,3

%A _N. J. A. Sloane_, Nov 16 2014