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Conjecturally the number of even integers the sum of two primes in exactly n ways.
5

%I #14 Dec 25 2016 00:25:10

%S 1,4,9,11,11,16,16,18,20,23,16,29,16,25,27,23,22,25,35,29,26,25,27,27,

%T 27,33,28,44,35,21,29,35,38,33,39,37,34,35,31,31,28,41,37,32,44,35,37,

%U 41,44,33,37,32,47,39,43,47,33,37,48,41,37,48,34,35,47,36,29,36,46,44,43,38,48

%N Conjecturally the number of even integers the sum of two primes in exactly n ways.

%H T. D. Noe, <a href="/A000974/b000974.txt">Table of n, a(n) for n = 0..5000</a>

%t f[n_] := Length[ Select[2n - Prime[ Range[ PrimePi[n]]], PrimeQ]]; a = Table[0, {75}]; Do[c = f[n]; If[c < 75, a[[c + 1]]++ ], {n, 5000}]; a (* _Robert G. Wilson v_, using Paul Abbott's coding in A002375, Apr 07 2005 *)

%Y Cf. A000954, A001172, A002375.

%K nonn

%O 0,2

%A _Bill Gosper_