OFFSET
0,1
COMMENTS
a(n) = T(n, 2), array T as in A049627.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
FORMULA
O.g.f.: -(x+2)(x^2-x-1)/((1-x)^2*(1+x)). - R. J. Mathar, Aug 13 2008
MATHEMATICA
Join[{2}, Select[Range[4, 100], MemberQ[{0, 2}, Mod[#, 3]]&]] (* or *) With[{nn=100}, Join[{2}, Riffle[Range[5, nn, 3], Range[6, nn, 3]]]] (* Harvey P. Dale, Jul 14 2012 *)
PROG
(PARI) x='x+O('x^20); Vec(-(x+2)*(x^2-x-1)/((1-x)^2*(1+x))) \\ G. C. Greubel, Dec 15 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Terms a(38) onward added by G. C. Greubel, Dec 15 2017
STATUS
approved