%I A118374
%S A118374 1,2,3,7,8,9,10,11,17,18,19,23,24,25,26,27,28,29,30,31,41,42,43,47,48,
%T A118374 49,50,51,57,58,59,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,
%U A118374 97,98,99,103,104,105,106,107,113,114,115,119,120,121,122,123,124,125
%N A118374 Lexigraphically earliest positive integer sequence no two terms of which 
               sum to a term of {1,7,23,63,159,...} = {n*2^n-1}, n=1,2,3,... The 
               first differences are given in A119350.
%C A118374 a(1)=1 and, for n>1, a(n) is the smallest integer greater than a(n-1) 
               such that a(n)+a(i) is not of the form k*2^k-1 for i=1,..., n-1 and 
               for any integer k>0.
%F A118374 It appears that a(n)=a(n-1)+A119350(n).
%Y A118374 Cf. A114889, A119350.
%Y A118374 Sequence in context: A100072 A089008 A047534 this_sequence A154432 A047361 
               A037461
%Y A118374 Adjacent sequences: A118371 A118372 A118373 this_sequence A118375 A118376 
               A118377
%K A118374 nonn
%O A118374 1,2
%A A118374 John W. Layman (layman(AT)math.vt.edu), May 15 2006