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A127460 a(1)=1. a(n) = number of earlier terms a(k), 1<=k<=n-1, such that (k+a(k)) divides n. 2
1, 1, 1, 2, 0, 3, 0, 2, 2, 3, 1, 5, 1, 3, 2, 2, 3, 5, 0, 5, 2, 2, 2, 6, 3, 2, 2, 6, 1, 7, 0, 2, 2, 6, 3, 7, 1, 4, 2, 6, 1, 7, 1, 4, 3, 4, 0, 8, 2, 6, 5, 3, 0, 5, 3, 9, 2, 3, 2, 10, 2, 2, 4, 3, 3, 4, 2, 8, 4, 8, 0, 8, 1, 3, 4, 6, 3, 5, 1, 9, 2, 3, 2, 11, 6, 2, 2, 5, 2, 9, 4, 5, 3, 2, 4, 10, 1, 5, 5, 8, 0, 9, 1, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..104.

EXAMPLE

(a(1)+1) divides 10; (a(5)+5) divides 10; and (a(8)+8) divides 10. These 3 cases are the only cases where (a(k)+k) divides 10, for 1<=k<=9. So a(10)=3.

MATHEMATICA

f[l_List] := Block[{n = Length[l] + 1}, Append[l, Count[Table[Mod[n, k + l[[k]]], {k, n - 1}], 0]]]; Nest[f, {1}, 104] (* Ray Chandler, Jan 22 2007 *)

CROSSREFS

Cf. A127461, A127462.

Sequence in context: A194666 A325799 A229946 * A274021 A303711 A154109

Adjacent sequences:  A127457 A127458 A127459 * A127461 A127462 A127463

KEYWORD

nonn

AUTHOR

Leroy Quet, Jan 15 2007

EXTENSIONS

Extended by Ray Chandler, Jan 22 2007

STATUS

approved

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Last modified June 16 21:55 EDT 2021. Contains 345080 sequences. (Running on oeis4.)