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A214795
a(n) is the smallest k>=2 such that n divides Fibonacci(k-1)+21.
3
2, 2, 5, 5, 10, 5, 9, 5, 17, 12, 2, 5, 6, 9, 13, 17, 8, 17, 11, 53, 9, 2, 4, 5, 30, 6, 45, 17, 7, 33, 23, 41, 13, 8, 33, 17, 47, 11, 21, 53, 29, 9, 53, 23, 93, 33, 25, 17, 65, 30, 29, 23, 42, 45, 10, 17, 29, 21, 51, 53
OFFSET
1,1
COMMENTS
The n-th entry a(n) means that a(n) is the index of the first term in A000045+21 which n divides.
MATHEMATICA
skdf[n_]:=Module[{k=2}, While[!Divisible[Fibonacci[k-1]+21, n], k++]; k]; Array[ skdf, 60] (* Harvey P. Dale, Nov 25 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Art DuPre, Aug 03 2012
EXTENSIONS
Definition corrected. - R. J. Mathar, Aug 09 2012
STATUS
approved