%I #6 Mar 29 2017 20:28:55
%S 1,2,5,9,11,14,17,20,23,27,29,33,35,39,41,45,47,50,53,56,59,62,65,68,
%T 71,74,77,80,83,86,89,92,95,99,101,105,107,111,113,117,119,123,125,
%U 129,131,135,137
%N a(n) = c(n-1) + c(n-3) where c is the sequence of numbers not in a.
%H Ivan Neretin, <a href="/A022429/b022429.txt">Table of n, a(n) for n = 0..10000</a>
%t Fold[Append[#1, Plus @@ Complement[Range[Max@#1 + 3], #1][[{#2, #2 + 2}]]] &, {1, 2, 5}, Range[43]] (* _Ivan Neretin_, Mar 29 2017 *)
%Y Cf. A022424 and references therein.
%K nonn
%O 0,2
%A _Clark Kimberling_
%E Missing term a(20) = 59 added by _Ivan Neretin_, Mar 29 2017