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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
OFFSET
1,4
COMMENTS
a(15) is unknown, since there is no known Wieferich prime to base 47 (cf. Fischer link).
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
KEYWORD
nonn,hard,more
AUTHOR
Felix Fröhlich, Feb 05 2016
STATUS
approved