%I
%S 1,1,1,2,3,23,5,144,98,658
%N a(n) is the difference between the two smallest positive integers that you cannot obtain using the integers {1,2,...,n} at most once and the four operators +, , *, /.
%H G. Bannay, <a href="http://gilles.bannay.free.fr/jeux_us.html">LE COMPTE EST BON</a>
%H <a href="/index/Fo#4x4">Index entries for similar sequences</a>
%e a(4)=2 because 29 and 31 are the smallest numbers that you cannot obtain using {1,2,3,4} and the four operations and 3129 = 2.
%Y Cf. A060315.
%K hard,more,nonn
%O 1,4
%A Koksal Karakus (karakusk(AT)hotmail.com), Jun 07 2002
