A121293 a(n) = Bell(3*n+2).

2, 52, 4140, 678570, 190899322, 82864869804, 51724158235372, 44152005855084346, 49631246523618756274, 71339801938860275191172, 128064670049908713818925644, 281600203019560266563340426570, 746289892095625330523099540639146

Offset: 0

Author

Vladeta Jovovic, Aug 24 2006

Keywords

• easy
• nonn

Comments

Even Bell numbers. A000110 except A134715. - Vladimir Reshetnikov, Nov 02 2015

Links

• Robert Israel, Table of n, a(n) for n = 0..190

Crossrefs

Cf. A000110, A070906, A134715.

Programs

Maple

seq(combinat:-bell(3*k+2), k=0..20); # Robert Israel, Nov 02 2015

Mathematica

Table[ BellB[3*n + 2], {n, 0, 10}]  (* Jean-François Alcover, Dec 13 2012 *)

PARI

a000110(n) = n!*polcoeff(exp(exp(x+x*O(x^n))-1), n);
vector(20, n, n--; a000110(3*n+2)) \\ Altug Alkan, Nov 02 2015

Formula

E.g.f.: exp(-1)*Sum_{n>=0}(n^2*exp(n^3*x)/n!).