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 A227007 Numbers n such that n-1 is squarefree and every prime divisor of n-1 is in the sequence. 6
 2, 3, 4, 7, 8, 15, 22, 43, 44, 87, 130, 259, 302, 603, 904, 1807 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The complement of A227006. 1807 is the last term in this sequence. - Charles R Greathouse IV, Jun 27 2013 LINKS J. M. Grau, A. M. Oller-Marcén and J, Sondow, On the congruence 1^n+2^n+...+n^n == d (mod n), where d divides n, arXiv preprint arXiv:1309.7941, 2013 MATHEMATICA Needs["NumberTheory`NumberTheoryFunctions`"]; Is[2] = True; Is[{}] = True; Is[n_] := Is[n] = If[ListQ[n], Is[n[[1, 1]]] && Is[Rest[n]], SquareFreeQ[n - 1] && Is[fa[n - 1]]]; Select[1 + Range@10000, Is] CROSSREFS Cf. A227006. Sequence in context: A300486 A120611 A092063 * A126850 A007497 A126882 Adjacent sequences:  A227004 A227005 A227006 * A227008 A227009 A227010 KEYWORD nonn,fini,full AUTHOR José María Grau Ribas, Jun 27 2013 STATUS approved

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Last modified April 23 14:15 EDT 2019. Contains 322386 sequences. (Running on oeis4.)