%I #24 Aug 29 2018 14:25:18
%S 0,1,1,1,2,1,1,3,3,1,1,4,4,4,1,1,5,6,6,5,1,1,6,7,8,7,6,1,1,7,9,10,10,
%T 9,7,1,1,8,10,13,12,13,10,8,1,1,9,12,14,16,16,14,12,9,1,1,10,13,17,17,
%U 20,17,17,13,10,1,1,11,15,19,21,22,22,21,19,15,11,1,1,12,16,21,23,27,24,27
%N Array T read by diagonals; T(i,j) is the number of nonnegative slopes of lines determined by 2 lattice points in [ 0,i ] X [ 0,j ] if i > 0; T(0,j)=1 if j > 0; T(0,0)=0.
%C The infinity slope is not counted unless i=0 and j>0. - _Max Alekseyev_, Oct 23 2008
%H Max A. Alekseyev. On the number of two-dimensional threshold functions, arXiv:<a href="https://arxiv.org/abs/math/0602511">math/0602511</a> [math.CO], 2006-2010; SIAM J. Disc. Math. 24(4), 2010, pp. 1617-1631. doi:<a href="http://doi.org/10.1137/090750184">10.1137/090750184</a>.
%F For m,n > 0, T(m,n) = 1 + U(m,n) = 1 + Sum_{i=1..m, j=1..n, gcd(i,j)=1} 1. - _Max Alekseyev_, Oct 23 2008
%e Diagonals (each starting on row 1): {0}; {1,1}; {1,2,1}; ...
%Y Cf. A005598, A049703, A114043.
%K nonn,tabl,easy
%O 0,5
%A _Clark Kimberling_
%E More terms from _Max Alekseyev_, Oct 23 2008