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%I #5 Sep 04 2022 22:48:10
%S 1,1,3,5,9,11,17,21,33,35,41,43,65,69,81,85,129,131,137,139,161,163,
%T 169,171,257,261,273,277,321,325,337,341
%N Union of A145812 and A145818 with double repetition of 1, so that a(1)=1, a(2)=1
%C Theorem. For every even integer m there exists a representation of the form m=a(r)+a(s). If A(x) is the counting function of a(n)<=x, then A(x)=O(sqrt(x))and Omega(sqrt(x)). Conjecture. The sequence is minimal in the following sense: if any sequence has the counting function B(x)<=A(x) for all x>=1 and B(x) < A(x) for x>=x_0, then there exists an even integer N which is not expressible as a sum of two terms of such sequence.
%Y Cf. A145812, A145818.
%K nonn
%O 1,3
%A _Vladimir Shevelev_, Oct 20 2008