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%I #12 Feb 06 2016 17:10:43
%S 0,0,0,3,1,4,2,6,6,7,4,9,5,10,11,12,9,14,11,14,18,17,14,20,18,20,17,
%T 23,18,22,22,26,23,29,26,26,26,30,28,36,23,34,30,34,31,43,30,40,33,37,
%U 43,45,31,46,42,44,40,48,42,48,39,52,47,53
%N a(1)=0. a(n) = number of earlier terms of the sequence which when added to n produce a composite number.
%H G. C. Greubel, <a href="/A115208/b115208.txt">Table of n, a(n) for n = 1..10000</a>
%e Adding 7 to the first 6 terms of the sequence gives [7,7,7,10,8,11]. Of these terms, two are composite, so a(7) = 2.
%t a = {0, 0}; For[n = 3, n < 90, n++, in = 0; For[j = 1, j < Length[a] + 1, j++, If[ ! PrimeQ[n + a[[j]]], in++ ]]; AppendTo[a, in]]; a (* _Stefan Steinerberger_, Jun 03 2007 *)
%Y Cf. A115207, A115209, A115210.
%K nonn
%O 1,4
%A _Leroy Quet_, Jan 16 2006
%E More terms from _Stefan Steinerberger_, Jun 03 2007