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
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Oct 16 2009
EXTENSIONS
New definition from R. J. Mathar, Jan 05 2011
STATUS
approved