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 A234952 Apply the map k -> L(k)/gcd(L(k),k-1) to the sequence A007850 of Giuga numbers, where L(k) is the Carmichael lambda function A002322. 0
 4, 60, 120, 2320, 1552848, 10080, 139714902540, 93294624780, 228657996794220, 4756736241732916394976, 20024071474861042488900, 2176937111336664570375832140, 15366743578393906356665002406454800354974137359272445859047945613961394951904884493965220 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS J. M. Grau and A. M. Oller-MarcĂ©n, On the congruence sum_{j=1}^{n-1} j^{k(n-1)} == -1 (mod n); k-strong Giuga and k-Carmichael numbers, arXiv preprint arXiv:1311.3522, 2013 CROSSREFS Cf. A007850, A002322. Sequence in context: A058173 A074835 A060492 * A112041 A210425 A002060 Adjacent sequences:  A234949 A234950 A234951 * A234953 A234954 A234955 KEYWORD nonn AUTHOR N. J. A. Sloane, Jan 12 2014 STATUS approved

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Last modified May 15 21:44 EDT 2021. Contains 343929 sequences. (Running on oeis4.)