A105335 a(n) = n*(n+1)/2 mod 64.

0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 2, 14, 27, 41, 56, 8, 25, 43, 62, 18, 39, 61, 20, 44, 5, 31, 58, 22, 51, 17, 48, 16, 49, 19, 54, 26, 63, 37, 12, 52, 29, 7, 50, 30, 11, 57, 40, 24, 9, 59, 46, 34, 23, 13, 4, 60, 53, 47, 42, 38, 35, 33, 32, 32, 33, 35, 38, 42, 47, 53, 60, 4, 13

Offset: 0

Author

Oscar Takeshita, May 01 2005

Keywords

• nonn

Comments

Periodic with period length 128. - Ray Chandler, Apr 18 2025

Links

• Index entries for linear recurrences with constant coefficients, order 127.

Crossrefs

See A105198 for further information.

Cf. A018819.

Programs

Mathematica

Mod[Accumulate[Range[0,80]],64] (* Harvey P. Dale, Jul 17 2020 *)

Formula

G.f. = p(x)/q(x) where p(x) has degree 124, and q(x) = (x-1)*(x^2+1)*(x^4+1)*(x^8+1)*(x^16+1)*(x^32+1)*(x^64+1), which has coefficients which are alternately +1 and -1 (when expanded). Compare the g.f. for binary partitions, A018819. - Harvey P. Dale and N. J. A. Sloane, Jul 17 2020