A187892 a(0)=0, a(1)=6, a(n)=a(n-1)+a(n-2)-1.

0, 6, 5, 10, 14, 23, 36, 58, 93, 150, 242, 391, 632, 1022, 1653, 2674, 4326, 6999, 11324, 18322, 29645, 47966, 77610, 125575, 203184, 328758, 531941, 860698, 1392638, 2253335, 3645972, 5899306, 9545277, 15444582, 24989858, 40434439, 65424296, 105858734

Offset: 0

Author

Vladimir Joseph Stephan Orlovsky, Mar 15 2011

Keywords

• nonn
• easy

Links

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

Crossrefs

Cf. A000071, A001611, A001612, A187890.

Programs

Mathematica

Join[{a=0,b=6},Table[c=a+b-1;a=b;b=c,{n,100}]]
LinearRecurrence[{2,0,-1},{0,6,5},40] (* Harvey P. Dale, Aug 17 2019 *)

Formula

G.f.: -x^2*(-6+7*x) / ( (x-1)*(x^2+x-1) ). - R. J. Mathar, Mar 15 2011

a(n) = 1+A022130(n-3), n>2. - R. J. Mathar, Mar 15 2011