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%I #4 Jan 27 2024 19:50:49
%S 0,2,2,6,14,39,125,399,1310,4356,14970,51715,178832,635778,2290019,
%T 8106059,29234378,105635076,384409483,1408730050,5193316109,
%U 19170300330,71421970661,263893092145,984568438169,3686368605467,13838552783467,52008816746450
%N Number of solutions to +- 2 +- 3 +- 5 +- 7 +- ... +- prime(2*n) = prime(2*n).
%F a(n) = [x^prime(2*n)] Product_{k=1..2*n} (x^prime(k) + 1/x^prime(k)).
%t Table[Coefficient[Product[(x^Prime[k] + 1/x^Prime[k]), {k, 1, 2 n}], x, Prime[2 n]], {n, 1, 28}]
%Y Cf. A000040, A022894, A063890, A113040, A350695, A369390.
%K nonn
%O 1,2
%A _Ilya Gutkovskiy_, Jan 27 2024
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