A076285 Numbers of the form (6^{mr}-1)/(6^r-1) for positive integers m, r.

1, 7, 37, 43, 217, 259, 1297, 1333, 1555, 7777, 9331, 46657, 46873, 47989, 55987, 279937, 335923, 1679617, 1680913, 1727605, 2015539, 10077697, 10124569, 12093235, 60466177, 60473953, 62193781, 72559411, 362797057, 435356467, 2176782337, 2176828993, 2178463249

Offset: 1

Author

N. J. A. Sloane, Nov 06 2002

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..9380
• T. Chinburg and M. Henriksen, Sums of k-th powers in the ring of polynomials with integer coefficients, Acta Arithmetica, 29 (1976), 227-250.

Programs

Maple

1, seq(seq((6^(m+r)-1)/(6^r-1), r = sort(convert(numtheory:-divisors(m),list),`>`)),m=0..15); # Robert Israel, May 02 2018