A079581 Consider pairs (r,s) such that the polynomial (x^r+1) divides (x^s+1) and 1 <= r < s. This sequence gives the s values; A079673 gives the r values.

3, 5, 6, 7, 9, 9, 10, 11, 12, 13, 14, 15, 15, 15, 17, 18, 18, 19, 20, 21, 21, 21, 22, 23, 24, 25, 25, 26, 27, 27, 27, 28, 29, 30, 30, 30, 31, 33, 33, 33, 34, 35, 35, 35, 36, 36, 37, 38, 39, 39, 39, 40, 41, 42, 42, 42, 43, 44, 45, 45, 45, 45, 45, 46, 47, 48, 49, 49, 50, 50, 51

Offset

1,1

Comments

(x^r+1) divides (x^s+1) iff s/r is an odd integer.

Links

Table of n, a(n) for n=1..71.

Example

9 is in the sequence twice because (x^1+1) and (x^3+1) divide (x^9+1).

Crossrefs

Cf. A079665, A079672, A079673.

Sequence in context: A114309 A324060 A323828 * A229858 A269020 A057716

Adjacent sequences: A079578 A079579 A079580 * A079582 A079583 A079584

Keyword

nonn

Author

Jose R. Brox (tautocrona(AT)terra.es), Jan 25 2003

Extensions

Edited by Don Reble, Jun 12 2003

Status

approved