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 A128171 Numbers n such that n divides 1 + Sum[ Prime[k]^7, {k,1,n} ]. 1
 1, 2, 4, 5, 6, 10, 12, 46, 1830, 2086, 6000, 7681, 8242, 15204, 43698, 52054, 154490, 211052, 392767, 4309540, 6452151, 8773101, 15166410, 26552623, 176656106, 180281161, 568507964, 608235488, 620790480, 1053296976, 1627363527, 3740702866, 20254119186 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(36) > 4*10^10. - Robert Price, Dec 03 2013 LINKS Robert Price, Table of n, a(n) for n = 1..35 MATHEMATICA s = 1; Do[s = s + Prime[n]^7; If[ Mod[s, n] == 0, Print[n]], {n, 1000000}] CROSSREFS Cf. A085450 = smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n. Cf. A007504, A045345, A171399, A128165, A233523, A050247, A050248. Cf. A024450, A111441, A217599, A128166, A233862, A217600, A217601. Sequence in context: A233193 A177911 A127092 * A233768 A240748 A171165 Adjacent sequences:  A128168 A128169 A128170 * A128172 A128173 A128174 KEYWORD hard,nonn AUTHOR Alexander Adamchuk, Feb 22 2007, Feb 23 2007 EXTENSIONS More terms from Sean A. Irvine, Jan 18 2011 a(27)-a(35) from Robert Price, Dec 03 2013 STATUS approved

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Last modified June 24 17:58 EDT 2019. Contains 324330 sequences. (Running on oeis4.)