OFFSET
0,1
REFERENCES
R. K. Guy, personal communication.
LINKS
FORMULA
G.f.: ( 2+x-2*x^2 ) / ( (x-1)*(3*x^2+x-1) ). - R. J. Mathar, Feb 11 2016
MATHEMATICA
LinearRecurrence[{2, 2, -3}, {2, 5, 12}, 50] (* Harvey P. Dale, Jan 19 2021 *)
PROG
(Magma) I:=[2, 5, 12]; [n le 3 select I[n] else 2*Self(n-1) + 2*Self(n-2) - 3*Self(n-3): n in [1..30]]; // Wesley Ivan Hurt, Dec 27 2021
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved