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%I #46 Nov 03 2016 12:43:49
%S 1,2,3,5,6,9,9,13,11,17,20,17,10,32,16,23,26,30,25,21,55,38,30,27,25,
%T 34,57,19,83,49,44,40,39,60,37,77,54,57,27,43,79,67,45,110,42,93,79,
%U 79,43,85,46,90,96,41,54,96,127,107,63,78,181,67,78,72,189,51,77,103
%N a(n) is the number of distinct integers of the form x^2-x-prime(n) for 0<=x<=prime(n)+1 whose absolute value is prime.
%e a(2)=2 because prime(2)=3 and x^2 - x - 3 generates {-3, -3, -1, 3, 9}. This contains two integers, -3 and 3, whose absolute value is prime.
%e a(14)=32 because prime(14)=43 and x^2 - x - 43 generates 32 prime numbers for x = 0..44.
%o (PARI) isaprime(x) = isprime(x) || isprime(-x);
%o nbp(n) = {v = vector(prime(n)+2, x, x--; x^2-x-prime(n)); vp = select(x->isaprime(x), v); vp = Set(vp); #vp;} \\ _Michel Marcus_, Sep 13 2016
%Y Cf. A014556, A253827.
%K nonn
%O 1,2
%A _Charles Kusniec_, Sep 12 2016
%E More terms from _Michel Marcus_, Sep 13 2016
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