OFFSET
0,2
LINKS
Ivan Neretin, Table of n, a(n) for n = 0..10000
MATHEMATICA
Fold[Append[#1, Plus @@ Complement[Range[Max@#1 + 3], #1][[{#2, #2 + 2}]]] &, {1, 2, 7}, Range[43]] (* Ivan Neretin, Mar 29 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved