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A023174
Numbers k such that Fibonacci(k) == 2 (mod k).
2
1, 3, 6, 77, 93, 123, 143, 213, 237, 267, 453, 483, 573, 597, 627, 717, 723, 813, 843, 933, 1077, 1203, 1227, 1293, 1317, 1347, 1437, 1517, 1563, 1707, 1763, 1797, 1803, 1893, 1923, 2157, 2253, 2283, 2307, 2427, 2517, 2643, 2691, 2733, 2757, 2787, 2973, 3021
OFFSET
1,2
LINKS
MATHEMATICA
Select[Range[3100], Mod[Fibonacci[#]-2, #]==0&] (* Harvey P. Dale, Sep 22 2021 *)
PROG
(PARI) is(n)=((Mod([1, 1; 1, 0], n))^n)[1, 2]==2 \\ Charles R Greathouse IV, Oct 28 2014
CROSSREFS
Cf. A000045.
Sequence in context: A205081 A282175 A182966 * A350992 A213138 A364798
KEYWORD
nonn
STATUS
approved