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A205781
Least positive integer j such that n divides C(k)-C(j), where k, as in A205780, is the least number for which there is such a j, and C=A007598 (squared Fibonacci numbers).
0
1, 1, 1, 1, 2, 1, 2, 1, 1, 2, 3, 1, 4, 1, 2, 3, 6, 4, 2, 2, 2, 1, 2, 1, 4, 4, 3, 1, 5, 2, 3, 3, 2, 6, 5, 4, 3, 7, 4, 3, 8, 1, 3, 1, 1, 3, 6, 4, 3, 4, 6, 4, 2, 3, 3, 1, 2, 3, 3, 2, 12, 4, 1, 2, 7, 1, 2, 6, 10, 6, 2, 4, 2, 16, 4, 7, 1, 5, 4, 3, 5, 6, 11, 1, 7, 3, 4, 1, 8, 1, 5, 3, 4, 4, 3, 2, 5
OFFSET
1,5
COMMENTS
For a guide to related sequences, see A204892.
EXAMPLE
1 divides C(2)-C(1) -> k=2, j=1
2 divides C(3)-C(1) -> k=3, j=1
3 divides C(2)-C(1) -> k=2, j=1
4 divides C(3)-C(1) -> k=3, j=1
5 divides C(3)-C(2) -> k=3, j=2
MATHEMATICA
s = Table[(Fibonacci[n + 1])^2, {n, 1, 120}];
lk = Table[
NestWhile[# + 1 &, 1,
Min[Table[Mod[s[[#]] - s[[j]], z], {j, 1, # - 1}]] =!= 0 &], {z, 1,
Length[s]}]
Table[NestWhile[# + 1 &, 1,
Mod[s[[lk[[j]]]] - s[[#]], j] =!= 0 &], {j, 1, Length[lk]}]
(* Peter J. C. Moses, Jan 27 2012 *)
CROSSREFS
Sequence in context: A266476 A081327 A363279 * A357982 A280444 A030422
KEYWORD
nonn
AUTHOR
Clark Kimberling, Feb 01 2012
STATUS
approved