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A275001
Expansion of 1/(1 - Sum_{k>=1} x^(prime(k)^2)).
0
1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 2, 0, 0, 1, 3, 1, 0, 1, 4, 3, 0, 1, 6, 6, 1, 1, 8, 10, 4, 1, 10, 17, 10, 2, 12, 27, 20, 6, 14, 40, 38, 16, 17, 56, 68, 36, 25, 76, 114, 75, 43, 101, 180, 147, 81, 137, 273, 271, 159, 194, 401, 471, 313, 292, 579, 782, 601, 472, 832, 1251, 1109, 816
OFFSET
0,14
COMMENTS
Number of compositions (ordered partitions) of n into squares of primes (A001248).
From Ilya Gutkovskiy, Feb 12 2017: (Start)
Conjecture(1): every number > 23 is the sum of at most 8 squares of primes.
Conjecture(2): every number > 131 can be represented as a sum of 13 squares of primes. (End)
FORMULA
G.f.: 1/(1 - Sum_{k>=1} x^(prime(k)^2)).
EXAMPLE
a(17) = 3 because we have [4, 4, 9], [4, 9, 4] and [9, 4, 4].
MATHEMATICA
nmax = 85; CoefficientList[Series[1/(1 - Sum[x^Prime[k]^2, {k, 1, nmax}]), {x, 0, nmax}], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Dec 24 2016
STATUS
approved