OFFSET
0,4
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..500
FORMULA
E.g.f.: exp(sinh(x))*cosh(cosh(x)-1).
a(n) = sum{k=0..n, if(mod(n-k,2)=0, A048993(n,k), 0)}. - Paul Barry, May 19 2006
MAPLE
with(combinat):
b:= proc(n, i, t) option remember; `if`(n=0, t, `if`(i<1,
0, add(multinomial(n, n-i*j, i$j)/j!*b(n-i*j, i-1,
irem(t+`if`(irem(i, 2)=0, j, 0), 2)), j=0..n/i)))
end:
a:= n-> b(n$2, 1):
seq(a(n), n=0..30); # Alois P. Heinz, Mar 08 2015
MATHEMATICA
a[n_] := Sum[If[Mod[n-k, 2] == 0, StirlingS2[n, k], 0], {k, 0, n}]; Table[a[n], {n, 0, 30}] (* Jean-François Alcover, Mar 16 2015, after Paul Barry *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Aug 14 2004
EXTENSIONS
More terms from Emeric Deutsch, Nov 16 2004
STATUS
approved