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 A122140 Numbers n such that n divides sum of cubes of the first n primes A098999(n). 5
 1, 25, 537, 661, 5199, 113253, 240621, 5337048977, 17434578479, 34216676921 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(9) > 6*10^9. - Donovan Johnson, Oct 15 2012 a(11) > 10^11. - Robert Price, Mar 29 2013 LINKS OEIS Wiki, Sums of powers of primes divisibility sequences. EXAMPLE a(2) = 25 because 25 is the first number n>1 that divides sum of cubes of the first n primes. Mod[ A098999, 25] = Mod[ 2^3 + 3^3 + 5^3 + ... + 89^3 + 97^3, 25 ] = 0. MATHEMATICA s = 0; t = {}; Do[s = s + Prime[n]^3; If[ Mod[s, n] == 0, AppendTo[t, n]], {n, 1000000}]; t CROSSREFS Sequence in context: A282689 A282874 A144942 * A083191 A226299 A264378 Adjacent sequences:  A122137 A122138 A122139 * A122141 A122142 A122143 KEYWORD nonn AUTHOR Alexander Adamchuk, Aug 21 2006 EXTENSIONS a(8) from Donovan Johnson, Oct 15 2012 a(9)-a(10) from Robert Price, Mar 29 2013 STATUS approved

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Last modified June 4 10:04 EDT 2020. Contains 334825 sequences. (Running on oeis4.)