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 A088875 Cyclotomic(n,-n) is prime. 2
 1, 3, 4, 5, 6, 9, 12, 14, 17, 82, 86, 157, 158, 180, 210, 236, 245, 368, 462, 842, 1034, 3512, 3977, 8636 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This is a generalization of A056826. See A088817 for another generalization. Note that (n^n+1)/(n+1) = cyclotomic(n,-n) when n is prime. Also note that, for odd n>1, cyclotomic(n,-n) = cyclotomic(2n,n) and for n a multiple of 4, cyclotomic(n,-n) = cyclotomic(n,n). Some of the larger entries may only correspond to probable primes. LINKS Eric Weisstein's World of Mathematics, Cyclotomic Polynomial MATHEMATICA Do[p=Prime[n]; If[PrimeQ[Cyclotomic[n, -n]], Print[p]], {n, 100}] CROSSREFS Cf. A056826 ((n^n+1)/(n+1) is prime), A070519 (cyclotomic(n, n) is prime), A088817 (cyclotomic(2n, n) is prime). Sequence in context: A228895 A267322 A218929 * A022884 A105857 A103055 Adjacent sequences:  A088872 A088873 A088874 * A088876 A088877 A088878 KEYWORD hard,nonn AUTHOR T. D. Noe, Oct 20 2003 STATUS approved

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Last modified January 24 01:05 EST 2020. Contains 331178 sequences. (Running on oeis4.)