OFFSET
0,4
LINKS
FORMULA
EXAMPLE
a(8) = 3 because we have [6, 1, 1], [1, 6, 1] and [1, 1, 6].
MAPLE
b:= proc(n, t) option remember; local r, f, g;
if n=0 then t else r, f, g:=$0..2; while f<=n
do r, f, g:= r+b(n-f, 1-t), f+g, g+1 od; r fi
end:
a:= n-> b(n, 0):
seq(a(n), n=0..50); # Alois P. Heinz, Dec 03 2020
MATHEMATICA
nmax = 43; CoefficientList[Series[(1/2) (1/(1 - Sum[x^(k (k + 1)/2), {k, 1, nmax}]) - 1/Sum[x^(k (k + 1)/2), {k, 0, nmax}]), {x, 0, nmax}], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Dec 03 2020
STATUS
approved