%I #15 Oct 22 2019 12:27:07

%S 0,2,3,5,7,8,9,12,14,15,18,20,21,23,24,25,27,29,32,33,34,35,38,42,44,

%T 45,47,48,52,53,54,57,59,60,62,63,65,70,71,74,75,77,78,79,80,84,88,89,

%U 90,92,93,96,98,99,102,104,105,107,110,113,114,115,117,119

%N Nonnegative numbers of the form 8*T(x) - T(y) with 0 <= x, 0 <= y, where T() denotes a triangular number.

%C When incremented by 1 this is also the difference between an odd square (1 + 8*T) and a triangular number T.

%F a(n) = A175035(n) - 1.

%e 8*A000217(1) - A000217(2) = 8*1 - 3 = 5 = a(4).

%t T[n_] := n (n + 1)/2;Select[Union[Flatten[Table[8 T[x] - T[y], {x, 0, 15}, {y, 0, 100}]]],115 >= # >= 0 &]

%Y Cf. A000217 (T), A175035, A016754 (odd squares).

%K nonn

%O 1,2

%A _Ralf Steiner_, Oct 21 2019