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 A268479 For p = prime(n), number of primes (including p) in the trajectory of p under the procedure in A244550, also allowing the Wieferich prime 2, that are not terms of a repeating cycle. 3
 0, 0, 1, 2, 0, 1, 1, 1, 2, 1, 3, 1, 1, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS a(15) is unknown, since there is no known Wieferich prime to base 47 (cf. Fischer link). LINKS Table of n, a(n) for n=1..14. R. Fischer, Thema: Fermatquotient B^(P-1) == 1 (mod P^2) EXAMPLE The trajectory of 31 starts 31, 7, 5, 2, 1093, 2, 1093, 2, 1093, ...., entering a repeating cycle consisting of the terms 2 and 1093. There are three terms before the cycle, so a(11) = 3. CROSSREFS Cf. A244550, A252801, A252802, A252812. Sequence in context: A287356 A029402 A330443 * A035196 A287475 A158020 Adjacent sequences: A268476 A268477 A268478 * A268480 A268481 A268482 KEYWORD nonn,hard,more AUTHOR Felix Fröhlich, Feb 05 2016 STATUS approved

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Last modified March 3 15:08 EST 2024. Contains 370512 sequences. (Running on oeis4.)