OFFSET
0,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..500
FORMULA
E.g.f.: exp(sinh(x)+(cosh(x)-cos(x))/2).
MAPLE
a:= proc(n) option remember; `if`(n=0, 1, add(`if`(
irem(j, 4)=0, 0, binomial(n-1, j-1)*a(n-j)), j=1..n))
end:
seq(a(n), n=0..30); # Alois P. Heinz, Mar 17 2015
MATHEMATICA
a[n_] := a[n] = If[n == 0, 1, Sum[If[Mod[j, 4] == 0, 0, Binomial[n - 1, j - 1]*a[n - j]], {j, 1, n}]]; Table[a[n], {n, 0, 30}] (* Jean-François Alcover, Jan 20 2016, after Alois P. Heinz *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Christian G. Bower, Jan 18 2006
STATUS
approved