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%I #12 Oct 30 2013 14:08:50
%S 2,67,3,349,79,439,21559,14713,13,8123233,223,3468214093
%N Least prime p such that x^2 + 3*x + p produces primes for x = 0..n-1 but not x = n.
%C a(39) = 43 and all other terms > 128865958933.
%H R. A. Mollin, <a href="http://www.jstor.org/stable/2975080">Prime-producing quadratics</a>, Amer. Math. Monthly 104 (1997), 529-544.
%t Table[p = 2; While[! (Union[Table[PrimeQ[x^2 + 3*x + p], {x, 0, n - 1}]] == {True} && PrimeQ[n^2 + 3*n + p] == False), p = NextPrime[p]]; p, {n, 9}] (* _T. D. Noe_, Oct 29 2013 *)
%Y Cf. A164926.
%K nonn,more
%O 1,1
%A _Zak Seidov_, Oct 27 2013
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