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 A137664 (p + 1)^p - 1 for p = prime[n]. 2
 8, 63, 7775, 2097151, 743008370687, 793714773254143, 2185911559738696531967, 5242879999999999999999999, 55572324035428505185378394701823, 6863037736488299999999999999999999999999999 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS p^2 divides a(n) = (p + 1)^p - 1, p = Prime[n]. Quotients a(n)/Prime[n]^2 are listed in A137665(n) = {2,7,311,42799,6140565047,4696537119847,7563707819165039903,...}. Least prime factors of A137665(n) = a(n)/Prime[n]^2 are listed in A128456(n) = {2,7,311,127,23,157,7563707819165039903,...}. Largest prime factors A137665(n) = a(n)/Prime[n]^2 are listed in A137666(n) = {2,7,311,337,266981089,29914249171,7563707819165039903,...}. LINKS FORMULA a(n) = (Prime[n] + 1)^Prime[n] - 1. MATHEMATICA Table[ (Prime[n] + 1)^Prime[n] - 1, {n, 1, 15} ] CROSSREFS Cf. A128452, A128456, A128356, A128357, A137665, A137666. Sequence in context: A302399 A084096 A189943 * A317028 A014392 A008462 Adjacent sequences:  A137661 A137662 A137663 * A137665 A137666 A137667 KEYWORD nonn AUTHOR Alexander Adamchuk, Feb 04 2008 STATUS approved

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Last modified November 29 19:26 EST 2020. Contains 338769 sequences. (Running on oeis4.)