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A245456
Index of least Fibonacci number congruent to n mod 100.
0
0, 1, 3, 4, 192, 5, 81, 76, 6, 32, 15, 22, 216, 7, 111, 130, 168, 37, 27, 112, 60, 8, 117, 64, 198, 25, 99, 136, 204, 29, 105, 88, 174, 13, 9, 70, 222, 43, 93, 172, 30, 41, 63, 124, 12, 55, 21, 154, 186, 49, 75, 148, 36, 67, 129, 10, 162, 23, 87, 118, 180, 61, 57, 166, 72, 20, 141, 94, 24, 31, 45, 142, 54, 47, 51, 100, 48, 14, 33, 58, 210, 19, 123, 106, 18, 80, 39, 16, 66, 11, 135, 82, 156, 26, 69, 160, 42, 17, 147, 52
OFFSET
0,3
COMMENTS
The analogous sequence mod 1000 does not exist, because no Fibonacci number is congruent to, e.g., 4 mod 1000.
EXAMPLE
a(4) = 192 because F(192) = 5972304273877744135569338397692020533504 is 4 mod 100.
MATHEMATICA
Join[{0}, With[{fibs=Fibonacci[Range[230]]}, Flatten[Table[Position[fibs, _?(Mod[#, 100]==n&), {1}, 1], {n, 100}]]]] (* Harvey P. Dale, Mar 31 2015 *)
PROG
(PARI) a(n)=for(k=0, 222, if(fibonacci(k)%100==n, return(k)))
CROSSREFS
Cf. A023183.
Sequence in context: A082213 A097172 A042081 * A042275 A012861 A349885
KEYWORD
nonn,fini,full
AUTHOR
STATUS
approved