OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (4,0,1,-4).
FORMULA
G.f.: x*(2+x+x^2) / ( (x-1)*(4*x-1)*(1+x+x^2) ). - R. J. Mathar, Nov 21 2011
MATHEMATICA
LinearRecurrence[{4, 0, 1, -4}, {2, 9, 37, 150}, 40] (* Vincenzo Librandi, Jun 17 2012 *)
Module[{nn=30, c}, c=PadRight[{}, nn, {2, 1, 1}]; Table[FromDigits[Take[c, n], 4], {n, nn}]] (* Harvey P. Dale, May 06 2015 *)
PROG
(Magma) I:=[2, 9, 37, 150]; [n le 4 select I[n] else 4*Self(n-1)+Self(n-3)-4*Self(n-4): n in [1..30]]; // Vincenzo Librandi, Jun 17 2012
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved