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%I #10 Nov 07 2019 23:30:59
%S 1,1,3,1,3,5,1,5,7,1,3,5,7,9,1,3,5,7,9,11,1,7,11,13,1,3,5,7,9,11,13,
%T 15,1,3,5,7,9,11,13,15,17,1,5,11,13,17,19,1,3,5,7,9,11,13,15,17,19,21,
%U 1,3,7,9,11,13,17,19,21,23,1,5,7,11
%N Difference x-y of generator pairs (x,y) {x and y coprime and not both odd, x>y} of primitive Pythagorean triangles, sorted on values x+y (A126611), then on x-y.
%C This sequence gives the consecutive rows n = 2*m + 1, for m >= 1, of the array A216319. See the example. - _Wolfdieter Lang_, Oct 24 2019
%e From _Wolfdieter Lang_, Oct 24 2019: (Start)
%e From the array A216319 with n = 2*m + 1 = x + y, for m >= 1, the (x, y) values giving the terms of the present sequence as values x-y are:
%e m, n \ k 1 2 3 4 5 6 ... x-y values
%e --------------------------------------------------------------------
%e 1, 3: (2,1) 1
%e 2, 5: (3,2) (4,1) 1 3
%e 3, 7: (4,3) (5,2) (6,1) 1 3 5
%e 4, 9: (5,4) (7,2) (8,1) 1 5 7
%e 5, 11: (6,5) (7,4) (8,3) (9,2) (10,1) 1 3 5 7 9
%e 6, 13: (7,6) (8,5) (9,4) (10,3) (11,2) (12,1) 1 3 5 7 9 11
%e 7, 15: (8,7) (11,4) (13,2) (14,1) 1 7 11 13
%e ... (End)
%Y Cf. A094192, A094193, A126611, A216319.
%K nonn,easy
%O 1,3
%A _Lekraj Beedassy_, Feb 08 2007