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A300778
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Number of grid points visible from a corner of an m X n rectangular region on a square grid written as triangle T(m,n), 1 <= n <= m.
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3
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3, 4, 5, 5, 7, 9, 6, 8, 11, 13, 7, 10, 14, 17, 21, 8, 11, 15, 18, 23, 25, 9, 13, 18, 22, 28, 31, 37, 10, 14, 20, 24, 31, 34, 41, 45, 11, 16, 22, 27, 35, 38, 46, 51, 57, 12, 17, 24, 29, 37, 40, 49, 54, 61, 65, 13, 19, 27, 33, 42, 46, 56, 62, 70, 75, 85
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OFFSET
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1,1
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COMMENTS
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Same as A049687, but written as triangle.
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LINKS
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EXAMPLE
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The triangle starts:
3
4 5
5 7 9
6 8 11 13
7 10 14 17 21
8 11 15 18 23 25
9 13 18 22 28 31 37
...
T(3,2) = 7, X indicating hidden grid points:
0-----1#####X#####X
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2-----3-----4-----5
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X-----6-----X-----7
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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