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%I #11 Feb 28 2017 09:26:27
%S 0,0,0,0,0,8,0,0,6,24,0,0,6,22,40,0,0,2,20,46,64,0,0,2,20,44,70,96,0,
%T 0,2,8,42,76,98,136,0,0,2,8,34,74,104,138,176,0,0,2,8,22,72,110,148,
%U 186,208,0,0,2,4,18,56,112,146,188,234,264,0,0,2,4,18
%N Triangle read by rows: T(n,k), n>=k>=1, is the number of acute triangles with integer coordinates that have a bounding box of size n X k.
%C It appears that the main diagonal is 8*A014811.
%H Lars Blomberg, <a href="/A280653/b280653.txt">Table of n, a(n) for n = 1..9870</a> (the first 140 rows)
%e Triangle begins:
%e 0
%e 0,0
%e 0,0,8
%e 0,0,6,24
%e 0,0,6,22,40
%e 0,0,2,20,46,64
%e 0,0,2,20,44,70,96
%e 0,0,2,8,42,76,98,136
%e 0,0,2,8,34,74,104,138,176
%e 0,0,2,8,22,72,110,148,186,208
%e 0,0,2,4,18,56,112,146,188,234,264
%e 0,0,2,4,18,44,94,152,198,244,286,328
%e 0,0,2,4,18,32,86,150,196,254,296,342,392
%e -----
%e For n=3, k=3:
%e o.o o.. o.. .o. .o. .o. ..o ..o
%e ... ..o ..o o.. ..o ... o.. o..
%e .o. o.. .o. ..o o.. o.o .o. ..o
%e so T(3,3)=8
%e -----
%e For n=4, k=3:
%e o..o o..o o... .o.. ..o. ...o
%e .... .... ...o .... .... o...
%e .o.. ..o. o... o..o o..o ...o
%e so T(4,3)=6
%e -----
%e For n=6, k=3:
%e o..... .....o
%e .....o o.....
%e o..... .....o
%e so T(6,3)=2
%Y Cf. A190019.
%Y See A279415 for right isosceles triangles.
%Y See A280639 for obtuse isosceles triangles.
%Y See A279418 for acute isosceles triangles.
%Y See A279413 for all isosceles triangles.
%Y See A279433 for all right triangles.
%Y See A280652 for all obtuse triangles.
%Y See A279432 for all triangles.
%K nonn,tabl
%O 1,6
%A _Lars Blomberg_, Feb 25 2017
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