%I #8 Apr 09 2014 10:14:38
%S 1,1,2,3,5,8,13,21,6,30,24,55,31,87,56,144,88,233,145,379,234,614,380,
%T 995,615,1611,996,2608,1612,4221,2609,6831,4222,11054,6832,17887,
%U 11055,28943,17888,46832,28944,75777,46833,122611,75778,198390,122612,321003
%N a(1) = a(2) = 1. For n >=3, a(n) = the a(n-2)th integer, among those positive integers which are missing from the first (m-1) terms of the sequence, below a(n-1) if such a positive integer exists. Otherwise, a(n) = the a(n-2)th integer, among those positive integers which are missing from the first (m-1) terms of the sequence, above a(n-1).
%e The first 8 terms of the sequence are 1,1,2,3,5,8,13,21. Those integers which are missing from the first 8 terms of the sequence form the sequence 4,6,7,9,10,11,12,14,15,16,17,18,19,20,.. Counting down from a(8)=21 a total of a(7)=13 positions in this sequence of missing terms, we land on 6. So a(9) = 6.
%e There are fewer than a(8)=21 missing positive integers below a(9)=6, so we count UP to get a(10). a(10) is what we land on when counting up from 6 a total of a(8)=21 positions, skipping over terms which occur earlier in the sequence. So a(10) = 30.
%K easy,nonn
%O 1,3
%A _Leroy Quet_, May 09 2006
%E More terms from _Joshua Zucker_, Jul 27 2006