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%I #12 Sep 25 2019 03:32:46
%S 2,55,665,6545,85085,1616615,37182145
%N Least number k having exactly n prime divisors and the Stern polynomial B(k,x) is irreducible.
%C Ulas and Ulas tabulate these values and conjecture 6.5, p.20, that a(n) exists for all n.
%C See A125184 for the Stern polynomials. See A186891 for n such that the Stern polynomial B_n(x) is irreducible.
%H Maciej Ulas and Oliwia Ulas, <a href="http://arxiv.org/abs/1102.5109">On certain arithmetic properties of Stern polynomials</a>, arXiv:1102.5109 [math.CO], 2011.
%e a(1) = 2.
%e a(2) = 55 = 5 * 11.
%e a(3) = 665 = 5 * 7 * 19.
%e a(4) = 6545 = 5 * 7 * 11 * 17.
%e a(5) = 85085 = 5 * 7 * 11 * 13 * 17.
%e a(6) = 1616615 = 5 * 7 * 11 * 13 * 17 * 19.
%e a(7) = 37182145 = 5 * 7 * 11 * 13 * 17 * 19 * 23.
%Y Cf. A125184, A186891.
%K nonn,more
%O 1,1
%A _Jonathan Vos Post_, Feb 28 2011
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