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%I #14 Jun 25 2019 12:43:59
%S 0,1,0,1,4,3,6,5,8,9,8,11,12,11,14,15,16,15,18,19,18,21,22,23,24,25,
%T 24,27,26,29,30,31,32,31,34,33,36,37,38,39,40,39,42,41,44,43,46,47,48,
%U 47,50,51,50,53,54,55,56,55,58,59,58,61,62,63,62,65,66,67,68,67,70,71,72
%N Number of ways writing n-th prime as a sum of a prime and a nonprime.
%H T. D. Noe, <a href="/A062302/b062302.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A062602(A000040(n)) = number of [nonprime+prime] partitions of prime(n)
%t Table[c = 0; Do[i = Prime[k]; If[i + j == Prime[n] && ! PrimeQ[j], c = c + 1], {k, n - 1}, {j, Prime[n] - 1}]; c, {n, 73}] (* _Jayanta Basu_, Apr 22 2013 *)
%t nn = 100; mx = Prime[nn]; ps = Prime[Range[nn]]; notPs = Complement[Range[mx], ps]; t2 = Table[0, {Range[mx]}]; Do[s = i + j; If[s <= mx, t2[[s]]++], {i, ps}, {j, notPs}]; t2[[ps]] (* _T. D. Noe_, Apr 23 2013 *)
%Y Cf. A061358, A062602, A000040, A014092, A025584.
%K nonn
%O 1,5
%A _Labos Elemer_, Jul 05 2001