OFFSET
0,1
LINKS
FORMULA
a(n) = -2*(-1)^n + 6. - Paolo P. Lava, Oct 20 2006
From R. J. Mathar, Oct 20 2008: (Start)
a(n) = 4*A000034(n).
G.f.: 4(1+2x)/((1-x)(1+x)). (End)
MATHEMATICA
Table[4 + 4 Mod[n, 2], {n, 0, 50}] (* Jinyuan Wang, Feb 26 2020 *)
LinearRecurrence[{0, 1}, {4, 8}, 100] (* or *) PadRight[{}, 100, {4, 8}] (* Harvey P. Dale, Aug 29 2023 *)
PROG
(PARI) a(n)=4+n%2*4 \\ Charles R Greathouse IV, Dec 21 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved