OFFSET
1,3
LINKS
FORMULA
Exponents in expansion of Product_{k>=1} (1 + x^(k*(k+1)/2)^2).
EXAMPLE
37 is in the sequence because 37 = 1 + 36 = 1^2 + (1 + 2 + 3)^2 = 1^3 + 1^3 + 2^3 + 3^3.
MATHEMATICA
max = 800; f[x_] := Product[1 + x^(k (k + 1)/2)^2, {k, 1, 10}]; Exponent[#, x] & /@ List @@ Normal[Series[f[x], {x, 0, max}]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jul 14 2017
STATUS
approved