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 A309542 Numbers k such that A001414(k^3+1) is divisible by k. 2
 1, 2, 5, 7, 20, 24, 45, 54, 286, 1942, 30771000, 71149819, 106438598, 668274063 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(15) > 1.5*10^9. - Giovanni Resta, Aug 07 2019 LINKS EXAMPLE 5 is a member because the prime factorization of 5^3+1=126 is 2*3^2*7 and 2+3+3+7=15 is divisible by 5. MAPLE filter:= proc(n) local F, t;   F:= ifactors(n^3+1)[2];   add(t[1]*t[2], t=F) mod n = 0 end proc: select(f, [\$1..10000]); CROSSREFS Cf. A001414, A309534, A309544. Sequence in context: A096146 A041583 A143915 * A327322 A160820 A158357 Adjacent sequences:  A309539 A309540 A309541 * A309543 A309544 A309545 KEYWORD nonn,more AUTHOR J. M. Bergot and Robert Israel, Aug 06 2019 EXTENSIONS a(11)-a(14) from Giovanni Resta, Aug 07 2019 STATUS approved

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Last modified April 18 07:11 EDT 2021. Contains 343072 sequences. (Running on oeis4.)