%I #36 Aug 15 2017 20:34:44
%S 3,3,3,4,4,4,4,4,4,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,7,7,7,7,7,7,7,
%T 7,7,7,7,7,8,8,8,8,8,8,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
%U 9,10,10,10,10,10,10,10,10,10,10,10,10,10
%N Upper bound for certain restricted sumsets.
%D Bela Bajnok, Additive Combinatorics: A Menu of Research Problems, Manuscript, May 2017. See Corollary C.56.
%H Bela Bajnok, <a href="https://arxiv.org/abs/1705.07444">Additive Combinatorics: A Menu of Research Problems</a>, arXiv:1705.07444 [math.NT], May 2017. See Corollary C.56.
%F a(n) = floor( (sqrt(4*n + 9) + 3) / 2).
%t Table[Floor[(Sqrt[4*n + 9] + 3)/2], {n, 100}]
%Y Cf. A155934, A288583, A289434.
%K nonn
%O 1,1
%A _Robert Price_, Aug 13 2017