OFFSET
0,2
COMMENTS
A trisection of A024495. - Paul Curtz, Nov 18 2007
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (7,8).
FORMULA
a(n) = (4*8^n -(-1)^n)/3.
a(n) = J(3*n+2) = A001045(3*n)/3.
From Philippe Deléham, Nov 19 2007: (Start)
a(0)=1, a(1)=11, a(n+1) = 7*a(n) + 8*a(n-1) for n>=1 .
G.f.: (1+4*x)/(1-7*x-8*x^2). (End)
MATHEMATICA
f[n_] := (4*8^n - (-1)^n)/3; Array[f, 20, 0] (* Robert G. Wilson v, Aug 13 2011 *)
LinearRecurrence[{7, 8}, {1, 11}, 20] (* Harvey P. Dale, May 06 2012 *)
PROG
(Magma) [4*8^n/3-(-1)^n/3: n in [0..30]]; // Vincenzo Librandi, Aug 13 2011
(PARI) vector(30, n, n--; (4*8^n -(-1)^n)/3) \\ G. C. Greubel, Sep 16 2018
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Apr 09 2003
STATUS
approved