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%I #16 Oct 30 2023 07:42:24
%S 0,1,1,2,2,2,1,0,3,4,5,4,4,2,7,5,6,5,5,1,4,5,3,6,6,7,8,6,7,7,6,5,5,6,
%T 11,16,13,9,9,11,12,13,7,4,6,11,10,12,8,7,8,12,12,15,17,14,12,11,15,
%U 16,15,14,11,13,16,21,22,18,12,11,16,17,14,12,12,12,20,17,10,8,14,14,16,13,21
%N a(1)=0. a(n) = number of earlier terms a(k) (1 <=k <=n-1) where a(k)+n is a prime.
%H Michael De Vlieger, <a href="/A114898/b114898.txt">Table of n, a(n) for n = 1..10000</a> (first 2000 terms from T. D. Noe)
%e If we add 10 to each of the first 9 terms of the sequence, we get [10,11,11,12,12,12,11,10,13]. Of these only the three 11's and the 13 are primes. So a(10) = 4.
%t Fold[Append[#1, Count[#1 + #2, _?PrimeQ]] &, {0}, Range[2, 85]] (* _Michael De Vlieger_, Sep 28 2017 *)
%Y Cf. A108839, A114899, A123541
%K nonn
%O 1,4
%A _Leroy Quet_, Jan 05 2006
%E Corrected and extended by _T. D. Noe_, Apr 30 2007
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