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%I #2 Mar 30 2012 18:39:58
%S 1,1,2,1,3,4,2,1,5,3,6,7,8,4,2,1,9,10,11,12,5,3,6,7,13,14,8,4,15,2,16,
%T 17,18,19,20,1,9,10,11,12,21,22,23,5,3,6,24,25,26,27,28,29,7,13,14,8,
%U 4,15,30,31,32,33,34,35,36,2,16,17,18,19,20,1,37,38,39,40,41
%N A self-descriptive fractal sequence: the sequence contains every positive integer. If the first occurrence of each integer is deleted from the sequence, the resulting sequence is the same is the original (this process may be called "upper trimming").
%C This sequence describes the number of Xs that are dropped and the number of numbers written between dropped Xs (cf. A112382 and A112383).
%Y Cf. A112377, A112382, A112383.
%K nonn
%O 0,3
%A _Kerry Mitchell_, Dec 05 2005