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%I #16 Dec 19 2017 02:29:49
%S 0,1,0,1,2,1,2,2,2,4,1,3,3,4,3,6,2,6,4,6,4,8,3,9,5,9,4,9,5,11,7,9,7,
%T 13,6,15,7,10,9,14,8,16,10,14,10,16,9,19,11,18,10,17,11,21,13,18,12,
%U 20,13,25,15,18,15,24,14,27,15,19,17,26,16,28,18,25
%N Number of partitions of n into two prime parts or two nonprime parts.
%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F a(n) = Sum_{i=1..floor(n/2)} [A010051(i) = A010051(n-i)], where [] is the Iverson bracket.
%F a(n) = floor(n/2) - A062602(n).
%t Table[Sum[KroneckerDelta[(PrimePi[k] - PrimePi[k - 1]), (PrimePi[n - k] - PrimePi[n - 1 - k])], {k, Floor[n/2]}], {n, 80}]
%Y Cf. A010051, A062602.
%K nonn,easy
%O 1,5
%A _Wesley Ivan Hurt_, Oct 20 2017
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