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A128171 Numbers k such that k divides 1 + Sum_{j=1..k} prime(j)^7. 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(43) > 1.4*10^13. - Bruce Garner, Apr 07 2021
LINKS
Bruce Garner, Table of n, a(n) for n = 1..42 (first 35 terms from Robert Price)
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.
Sequence in context: A233193 A177911 A127092 * A233768 A240748 A171165
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 April 18 22:18 EDT 2024. Contains 371782 sequences. (Running on oeis4.)