1,3

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

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

Cf. A131880, A000225.

Sequence in context: A208515 A286880 A178030 * A172288 A134628 A064882

Adjacent sequences: A131876 A131877 A131878 * A131880 A131881 A131882

nonn,tabl

Leroy Quet, Jul 23 2007

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

approved