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%I #29 Jun 16 2016 07:24:13
%S 0,0,0,0,0,0,1,1,1,2,2,2,3,3,4,5,5,5,6,7,7,8,8,8,9,9,10,11,11,12,13,
%T 13,13,14,15,15,16,16,16,17,18,18,19,19,20,21,21,22,23,24,24,25,25,25,
%U 26,26,26,27,27,28,29,30,31,32,33,33,34,34,35,36,36
%N The number of unordered partitions {a,b} of 2n-1 such that a and b are composite.
%C Except for the initial terms, the same sequence as A210469.
%H J. Stauduhar, <a href="/A224710/b224710.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = n - 2 - primepi(2n-4) for n>1. - _Anthony Browne_, May 03 2016
%F a(A104275(n+2) + 1) = n. - _Anthony Browne_, May 25 2016
%e n=7: 13 has a unique representation as the sum of two composite numbers, namely 13 = 4+9, so a(7)=1.
%t Table[Length@ Select[IntegerPartitions[2 n - 1, {2}] /. n_Integer /; ! CompositeQ@ n -> Nothing, Length@ # == 2 &], {n, 71}] (* Version 10.2, or *)
%t Table[If[n == 1, 0, n - 2 - PrimePi[2 n - 4]], {n, 71}] (* _Michael De Vlieger_, May 03 2016 *)
%Y Subsequence of A224708. Cf. A210469.
%K nonn
%O 1,10
%A _J. Stauduhar_, Apr 16 2013