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 A191975 Lowest common multiple of all p-1, where prime p divides the n-th primary pseudoperfect number A054377(n). 1
 1, 2, 6, 42, 330, 235290, 310800, 1863851053628494074457830 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) is a factor of any exponent k > 0 such that 1^k + 2^k + ... + p^k == 1 (mod p), where p = A054377(n). LINKS J. Sondow and K. MacMillan, Reducing the ErdÅ‘s-Moser equation 1^n + 2^n + ... + k^n = (k+1)^n modulo k and k^2, Integers 11 (2011), #A34. FORMULA a(n) = lcm(p-1 : prime p | A054377(n)). EXAMPLE A054377(3) = 42 = 2*3*7, so a(3) = lcm(2-1, 3-1, 7-1) = lcm(1,2,6) = 6. CROSSREFS Cf. A054377. Sequence in context: A127071 A151333 A190626 * A074015 A074021 A050862 Adjacent sequences:  A191972 A191973 A191974 * A191976 A191977 A191978 KEYWORD nonn,more,hard,changed AUTHOR Kieren MacMillan, Jun 20 2011 STATUS approved

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Last modified March 21 22:41 EDT 2018. Contains 301043 sequences. (Running on oeis4.)