%I

%S 1,4,11,680,2,28,9,65,7,26,3,146,5,63,24,317,22,61,20,144,3038,18,6,

%T 59,16,8,142,10,14,57,12,315,55,140,53,6353,313,51,138,49,678,136,47,

%U 1441,45,134,43,311,676,41,132,13,39,309,15,37,17,130,19,35,3036,21,33,23

%N a(n) is the index k such that A111118(k) = n.

%e A111118(680) = 4, hence a(4) = 680.

%Y Cf. A111118, A111187.

%K nonn

%O 1,2

%A _Klaus Brockhaus_, Oct 25 2005