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%I
%S 3,3,4,4,4,5,5,6,6,6,6,8,8,8,8,9,9,9,9,10,10,11,12,12,12,12,12,13,14
%N Let A181741(n)=2^(t(n))-2^(k(n))-1, where k(n)>=1, t(n)>=k(n)+1. Then a(n)=t(n).
%Y Cf. A181741
%K nonn,uned
%O 1,1
%A _Vladimir Shevelev_, Nov 08 2010