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 A075723 Numbers n such that 1+n+n^6 is a prime. 5
 1, 2, 3, 6, 8, 15, 17, 29, 30, 32, 45, 48, 59, 72, 74, 80, 87, 128, 141, 153, 155, 156, 158, 176, 182, 191, 197, 210, 216, 230, 273, 284, 293, 305, 314, 356, 366, 380, 384, 399, 402, 407, 408, 410, 413, 420, 435, 443, 447, 450, 473, 479, 497 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For s = 5,8,11,14,17,20,..., n_s=1+n+n^s is always composite for any n>1. Also at n=1, n_s=3 is a prime for any s. So it is interesting to consider only the cases of s =/= 5,8,11,14,17,20,... and n>1. Here i consider the case s=6 and find several first n's making n_s a prime (or a probable prime). LINKS T. D. Noe, Table of n, a(n) for n=1..1000 EXAMPLE 15 is OK because at s=6, n=15, n_s=1+n+n^s=11390641 is a prime. CROSSREFS Cf. A002384, A049407, A049408. Sequence in context: A097097 A206370 A095162 * A138137 A129374 A209405 Adjacent sequences:  A075720 A075721 A075722 * A075724 A075725 A075726 KEYWORD nonn AUTHOR Zak Seidov, Oct 03 2002 STATUS approved

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