A131879 Triangle where row n contains the first n positive integers which are coprime to (2^n -1).

1, 1, 2, 1, 2, 3, 1, 2, 4, 7, 1, 2, 3, 4, 5, 1, 2, 4, 5, 8, 10, 1, 2, 3, 4, 5, 6, 7, 1, 2, 4, 7, 8, 11, 13, 14, 1, 2, 3, 4, 5, 6, 8, 9, 10, 1, 2, 4, 5, 7, 8, 10, 13, 14, 16, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 1, 2, 4, 8, 11, 16, 17, 19, 22, 23, 29, 31, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 1, 2, 4

Offset

1,3

Links

Table of n, a(n) for n=1..94.

Example

2^6 -1 = 63. So row 6 is the first 6 positive integers which are coprime to 63: (1,2,4,5,8,10).

Crossrefs

Cf. A131880, A000225.

Sequence in context: A208515 A286880 A178030 * A172288 A134628 A064882

Adjacent sequences: A131876 A131877 A131878 * A131880 A131881 A131882

Keyword

nonn,tabl

Author

Leroy Quet, Jul 23 2007

Extensions

More terms from R. J. Mathar, Aug 01 2007

Status

approved