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

%I #18 Nov 05 2015 02:41:28

%S 2,52,4140,678570,190899322,82864869804,51724158235372,

%T 44152005855084346,49631246523618756274,71339801938860275191172,

%U 128064670049908713818925644,281600203019560266563340426570,746289892095625330523099540639146

%N a(n) = Bell(3*n+2).

%C Even Bell numbers. A000110 except A134715. - _Vladimir Reshetnikov_, Nov 02 2015

%H Robert Israel, <a href="/A121293/b121293.txt">Table of n, a(n) for n = 0..190</a>

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

%p seq(combinat:-bell(3*k+2), k=0..20); # _Robert Israel_, Nov 02 2015

%t Table[ BellB[3*n + 2], {n, 0, 10}] (* _Jean-François Alcover_, Dec 13 2012 *)

%o (PARI) a000110(n) = n!*polcoeff(exp(exp(x+x*O(x^n))-1), n);

%o vector(20, n, n--; a000110(3*n+2)) \\ _Altug Alkan_, Nov 02 2015

%Y Cf. A000110, A070906, A134715.

%K easy,nonn

%O 0,1

%A _Vladeta Jovovic_, Aug 24 2006