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A279948 Expansion of (Sum_{k>=1} x^(prime(k)^2))^3. 0
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 3, 0, 0, 0, 0, 3, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 6, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 3, 0, 3, 0, 0, 6, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 6, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,18

COMMENTS

Number of ordered ways of writing n as the sum of three squares of primes (A001248).

LINKS

Table of n, a(n) for n=0..99.

Index entries for sequences related to sums of squares

FORMULA

G.f.: (Sum_{k>=1} x^(prime(k)^2))^3.

EXAMPLE

a(22) = 3 because we have [4, 9, 9], [9, 4, 9] and [9, 9, 4].

MATHEMATICA

nmax = 125; CoefficientList[Series[(Sum[x^Prime[k]^2, {k, 1, nmax}])^3, {x, 0, nmax}], x]

CROSSREFS

Cf. A001248, A063691, A098238.

Sequence in context: A320179 A035656 A325675 * A264009 A281155 A321432

Adjacent sequences:  A279945 A279946 A279947 * A279949 A279950 A279951

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Dec 24 2016

STATUS

approved

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Last modified December 2 06:44 EST 2020. Contains 338868 sequences. (Running on oeis4.)