OFFSET
1,1
LINKS
FORMULA
a(n) = ((34+7*sqrt(2))*(3-2*sqrt(2))^n+(34-7*sqrt(2))*(3+2*sqrt(2))^n)/4.
G.f.: x*(37-17*x)/(1-6*x+x^2). [corrected by Klaus Brockhaus, Sep 22 2009]
Limit_{n -> oo} a(n)/a(n-1) = 3+2*sqrt(2).
MATHEMATICA
LinearRecurrence[{6, -1}, {37, 205}, 30] (* Harvey P. Dale, Aug 18 2014 *)
PROG
(PARI) {m=19; v=concat([37, 205], vector(m-2)); for(n=3, m, v[n]=6*v[n-1]-v[n-2]); v}
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Klaus Brockhaus, Feb 11 2009, Feb 16 2009
STATUS
approved