A011870 a(n) = floor(n*(n-1)/17).

0, 0, 0, 0, 0, 1, 1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 14, 16, 18, 20, 22, 24, 27, 29, 32, 35, 38, 41, 44, 47, 51, 54, 58, 62, 66, 70, 74, 78, 82, 87, 91, 96, 101, 106, 111, 116, 121, 127, 132, 138, 144, 150, 156, 162, 168, 174, 181, 187, 194, 201, 208, 215, 222, 229, 237, 244, 252

Offset

0,8

Links

Table of n, a(n) for n=0..66.

Index entries for linear recurrences with constant coefficients, signature (2, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -2, 1).

Formula

G.f.: x^5(1-x+x^2)(1+x^8)/((1-x)^2*(1-x^17)). - R. J. Mathar, Jan 05 2009

Mathematica

Table[Floor[(n(n-1))/17], {n, 0, 70}] (* or *) LinearRecurrence[{2, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -2, 1}, {0, 0, 0, 0, 0, 1, 1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 14, 16, 18}, 70] (* Harvey P. Dale, Apr 11 2018 *)

Crossrefs

Sequence in context: A254636 A165763 A178877 * A361202 A284831 A261040

Adjacent sequences: A011867 A011868 A011869 * A011871 A011872 A011873

Keyword

nonn

Author

N. J. A. Sloane

Status

approved