A103380 a(n) = a(n-12) + a(n-13).

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 12, 15, 16, 16, 16, 16, 16, 16, 16, 16, 16, 17, 21, 27, 31, 32, 32, 32, 32, 32, 32, 32, 32, 33, 38, 48, 58, 63, 64, 64, 64, 64, 64, 64, 64, 65

Offset: 1

Author

Jonathan Vos Post, Feb 16 2005

Keywords

• easy
• nonn

Links

• T. D. Noe, Table of n, a(n) for n = 1..1000
• Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,0,1,1).

Crossrefs

Cf. A079398, A103372-A103379, A103400.

Programs

Maple

A103380 := proc(n) option remember ; if n <= 13 then 1; else procname(n-12)+procname(n-13) ; fi; end: for n from 1 to 120 do printf("%d,",A103380(n)) ; od: # R. J. Mathar, Aug 30 2008

Mathematica

LinearRecurrence[{0,0,0,0,0,0,0,0,0,0,0,1,1},{1,1,1,1,1,1,1,1,1,1,1,1,1},90] (* Harvey P. Dale, Jul 16 2012 *)

Formula

For n>13: a(n) = a(n-12) + a(n-13). a(1) = a(2) = ... = a(13) = 1.

G.f.: x*(1-x^12) / ((1-x)*(1-x^12-x^13)). - Colin Barker, Mar 27 2013

Extensions

Terms from a(11) on corrected by R. J. Mathar, Aug 30 2008