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 A279372 Expansion of (Sum_{k>=1} x^(prime(k)^2))^2. 0
 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 2, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,14 COMMENTS Number of ordered ways of writing n as the sum of two squares of primes (A001248). LINKS FORMULA G.f.: (Sum_{k>=1} x^(prime(k)^2))^2. a(n) = Sum_{i=1..n} A302048(i)*A302048(n-i). - Ridouane Oudra, Nov 21 2020 EXAMPLE a(13) = 2 because we have [4, 9] and [9, 4]. MATHEMATICA nmax = 125; CoefficientList[Series[(Sum[x^Prime[k]^2, {k, 1, nmax}])^2, {x, 0, nmax}], x] CROSSREFS Cf. A001248, A063725, A073610, A302048. Sequence in context: A230686 A341001 A221836 * A086077 A178408 A073345 Adjacent sequences:  A279369 A279370 A279371 * A279373 A279374 A279375 KEYWORD nonn AUTHOR Ilya Gutkovskiy, Dec 24 2016 STATUS approved

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Last modified May 25 02:55 EDT 2022. Contains 354047 sequences. (Running on oeis4.)