A166033 a(n) = 11/4 +11*n/2 + 29*(-1)^n/4.

1, 21, 12, 32, 23, 43, 34, 54, 45, 65, 56, 76, 67, 87, 78, 98, 89, 109, 100, 120, 111, 131, 122, 142, 133, 153, 144, 164, 155, 175, 166, 186, 177, 197, 188, 208, 199, 219, 210, 230, 221, 241, 232, 252, 243, 263, 254, 274, 265, 285, 276, 296, 287, 307, 298, 318

Offset

1,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

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

Formula

a(n) = 11*n-a(n-1) with n>1, a(1)=1.

G.f.: -x*(-1-20*x+10*x^2) / ( (1+x)*(x-1)^2 ). - R. J. Mathar, Jan 05 2011

E.g.f.: (1/2)*((11*x + 20)*cosh(x) + (11*x - 9)*sinh(x) - 20). - G. C. Greubel, Apr 24 2016

Mathematica

Table[11/4+11*n/2+29*(-1)^n/4, {n, 1, 60}] (* or *) LinearRecurrence[{1, 1, -1}, {1, 21, 12}, 60] (* Vincenzo Librandi, Mar 14 2012 *)

Prog

(Magma) [11/4+11*n/2+29*(-1)^n/4: n in [1..60]]; // Vincenzo Librandi, Mar 14 2012

Crossrefs

Sequence in context: A258083 A260527 A260529 * A228092 A071262 A083466

Adjacent sequences: A166030 A166031 A166032 * A166034 A166035 A166036

Keyword

nonn,easy

Author

Vincenzo Librandi, Oct 16 2009

Extensions

New definition from R. J. Mathar, Jan 05 2011

Status

approved