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A281477
Expansion of Sum_{k>=1} x^(prime(k)^2)/(1 + x^(prime(k)^2)) * Product_{k>=1} (1 + x^(prime(k)^2)).
1
0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 3, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
1,13
COMMENTS
Total number of parts in all partitions of n into distinct squares of primes (A001248).
FORMULA
G.f.: Sum_{k>=1} x^(prime(k)^2)/(1 + x^(prime(k)^2)) * Product_{k>=1} (1 + x^(prime(k)^2)).
EXAMPLE
a(38) = 3 because we have [25, 9, 4].
MAPLE
Primes:= select(isprime, [$1..20]):
g:= add(x^(p^2)/(1+x^(p^2)), p=Primes)*mul(1+x^(p^2), p=Primes):
S:= series(g, x, 20^2+1):
seq(coeff(S, x, n), n=1..20^2); # Robert Israel, Feb 08 2017
MATHEMATICA
nmax = 125; Rest[CoefficientList[Series[Sum[x^Prime[k]^2/(1 + x^Prime[k]^2), {k, 1, nmax}] Product[1 + x^Prime[k]^2, {k, 1, nmax}], {x, 0, nmax}], x]]
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jan 27 2017
STATUS
approved