A181288 Numbers of the form i*6^j-1 (i=1..5, j >= 0).

0, 1, 2, 3, 4, 5, 11, 17, 23, 29, 35, 71, 107, 143, 179, 215, 431, 647, 863, 1079, 1295, 2591, 3887, 5183, 6479, 7775, 15551, 23327, 31103, 38879, 46655, 93311, 139967, 186623, 233279, 279935, 559871, 839807, 1119743, 1399679, 1679615, 3359231, 5038847, 6718463, 8398079, 10077695, 20155391, 30233087

Offset: 1

Author

N. J. A. Sloane, Jan 25 2011

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,6,-6).

Crossrefs

Smallest number whose base b sum of digits is n: A000225 (b=2), A062318 (b=3), A180516 (b=4), A181287 (b=5), this sequence (b=6), A181303 (b=7), A165804 (b=8), A140576 (b=9), A051885 (b=10). - Jason Kimberley, Nov 02 2011

Programs

Mathematica

Union[Flatten[Table[i*6^j-1,{j,0,20},{i,5}]]] (* Harvey P. Dale, Nov 12 2012 *)

Formula

G.f.: x^2*(x^4+x^3+x^2+x+1) / ((x-1)*(6*x^5-1)). [Colin Barker, Feb 01 2013]