OFFSET
1,2
MATHEMATICA
nxt[{n_, a_, b_}]:={n+1, b, Abs[b+2a-n-1]}; Select[NestList[nxt, {1, 1, 1}, 200][[All, 2]], EvenQ] (* Harvey P. Dale, Aug 25 2022 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
More terms from James A. Sellers
Definition clarified by Harvey P. Dale, Aug 25 2022
STATUS
approved