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 A057939 Number of prime factors of 5^n + 1 (counted with multiplicity). 1
 2, 2, 4, 2, 3, 3, 4, 3, 6, 4, 5, 3, 4, 3, 7, 3, 4, 5, 5, 4, 10, 4, 4, 4, 5, 5, 10, 3, 4, 7, 5, 4, 9, 6, 7, 6, 5, 4, 8, 5, 6, 6, 6, 3, 10, 3, 5, 5, 7, 7, 10, 5, 5, 6, 7, 7, 9, 3, 6, 6, 6, 4, 16, 4, 8, 7, 3, 7, 9, 7, 5, 6, 5, 5, 13, 5, 9, 10, 6, 6, 14, 6, 5, 7, 9, 5, 9, 7, 5, 12, 8, 4, 10, 6, 9, 7, 7, 7, 12 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..451 S. S. Wagstaff, Jr., The Cunningham Project FORMULA a(n) = A057956(2n) - A057956(n). - T. D. Noe, Jun 19 2003 a(n) = A001222(A034474(n)). - Amiram Eldar, Feb 01 2020 MATHEMATICA PrimeOmega[5^Range[100]+1] (* Harvey P. Dale, Nov 27 2013 *) CROSSREFS Cf. A057934-A057941, A054992. Cf. A001222, A034474, A057956. Sequence in context: A238745 A092607 A221861 * A163371 A061338 A135714 Adjacent sequences:  A057936 A057937 A057938 * A057940 A057941 A057942 KEYWORD nonn AUTHOR Patrick De Geest, Oct 15 2000 STATUS approved

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Last modified May 15 02:21 EDT 2021. Contains 343909 sequences. (Running on oeis4.)