

A279071


Numbers k such that Fibonacci(k) == +1 (mod k).


2



1, 2, 3, 4, 7, 11, 13, 14, 17, 19, 22, 23, 26, 29, 31, 34, 37, 38, 41, 43, 46, 47, 53, 58, 59, 61, 62, 67, 71, 73, 74, 79, 82, 83, 86, 89, 94, 97, 101, 103, 106, 107, 109, 113, 118, 122, 127, 131, 134, 137, 139, 142, 146, 149, 151, 157, 158, 163, 166, 167, 173
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OFFSET

1,2


COMMENTS

The terms of this sequence are 1, every prime except 5, every "twice prime" except 6 and 10, and the terms of A279072, i.e., {323, 572, 646, 754, 2737, 3782, 4181, 5474, 5777, 6479, ...}.


LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000


EXAMPLE

1 is in the sequence because Fibonacci(1) mod 1 = 1 mod 1 = 0 and +1 mod 1 = 0.
2 is in the sequence because Fibonacci(2) mod 2 = 1 mod 2 = 1.
3 is in the sequence because Fibonacci(3) mod 3 = 2 mod 3 = 2 and 1 mod 3 = 2.


MATHEMATICA

Select[Range[200], MemberQ[{1, #  1}, Mod[Fibonacci[#], #]] &] (* Amiram Eldar, Jun 13 2020 *)


CROSSREFS

Cf. A000045, A279072.
Sequence in context: A226387 A102282 A232543 * A171027 A348792 A064933
Adjacent sequences: A279068 A279069 A279070 * A279072 A279073 A279074


KEYWORD

nonn


AUTHOR

Jon E. Schoenfield, Dec 30 2016


STATUS

approved



