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A122140
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Numbers n such that n divides sum of cubes of the first n primes A098999(n).
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25
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OFFSET
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1,2
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COMMENTS
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a(9) > 6*10^9. - Donovan Johnson, Oct 15 2012
a(11) > 10^11. - Robert Price, Mar 29 2013
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LINKS
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Table of n, a(n) for n=1..10.
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EXAMPLE
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a(2) = 25 because 25 is the first number n>1 that divides sum of cubes of the first n primes. Mod[ A098999[25], 25] = Mod[ 2^3 + 3^3 + 5^3 + ... + 89^3 + 97^3, 25 ] = 0.
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MATHEMATICA
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s = 0; t = {}; Do[s = s + Prime[n]^3; If[ Mod[s, n] == 0, AppendTo[t, n]], {n, 1000000}]; t
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CROSSREFS
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Cf. A098999, A007504, A045345, A024450, A111441, A122102, A122140, A122103, A122142.
Sequence in context: A000497 A028341 A144942 * A083191 A015679 A014909
Adjacent sequences: A122137 A122138 A122139 * A122141 A122142 A122143
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KEYWORD
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nonn
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AUTHOR
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Alexander Adamchuk, Aug 21 2006
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EXTENSIONS
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a(8) from Donovan Johnson, Oct 15 2012
a(9)-a(10) from Robert Price, Mar 29 2013
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STATUS
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approved
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