OFFSET
0,1
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (3,-2).
FORMULA
a(n) = A173786(n+4, 4).
a(n) = 3*a(n-1) - 2*a(n-2), a(0)=32, a(1)=48. - Vincenzo Librandi, Dec 28 2010
From G. C. Greubel, Jul 08 2021: (Start)
G.f.: 16*(2 - 3*x)/((1-x)*(1-2*x)).
E.g.f.: 16*(exp(2*x) + exp(x)). (End)
MATHEMATICA
16*(2^Range[0, 30] +1) (* or *) LinearRecurrence[{3, -2}, {32, 48}, 30] (* Harvey P. Dale, Jun 08 2017 *)
PROG
(Magma) I:=[32, 48]; [n le 2 select I[n] else 3*Self(n-1) - 2*Self(n-2): n in [1..41]]; // G. C. Greubel, Jul 08 2021
(Sage) [16*(2^n +1) for n in (0..40)] # G. C. Greubel, Jul 08 2021
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Reinhard Zumkeller, Feb 28 2010
STATUS
approved