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A272626
Array read by antidiagonals: T(n,k) = number of ways to choose 3 distinct points from an n X k rectangular grid so that they form a right isosceles triangle of nonzero area.
3
0, 0, 0, 0, 4, 0, 0, 10, 10, 0, 0, 16, 28, 16, 0, 0, 22, 50, 50, 22, 0, 0, 28, 74, 96, 74, 28, 0, 0, 34, 98, 150, 150, 98, 34, 0, 0, 40, 122, 208, 244, 208, 122, 40, 0, 0, 46, 146, 268, 350, 350, 268, 146, 46, 0, 0, 52, 170, 328, 464, 516, 464, 328, 170, 52, 0
OFFSET
1,5
COMMENTS
A271910(n) = A272624(n) + A272625(n) + a(n).
LINKS
FORMULA
T(n,k) = 2*T(n,k-1)-T(n,k-2) for k > max(5,(n-1)^2).
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Chai Wah Wu, May 07 2016
STATUS
approved