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A191973
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Irregular triangle read by rows: row n consists of n and the positive integers m where m-n divides m*n.
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8
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1, 2, 1, 2, 3, 4, 6, 2, 3, 4, 6, 12, 2, 3, 4, 5, 6, 8, 12, 20, 4, 5, 6, 10, 30, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 18, 24, 42, 6, 7, 8, 14, 56, 4, 6, 7, 8, 9, 10, 12, 16, 24, 40, 72, 6, 8, 9, 10, 12, 18, 36, 90, 5, 6, 8, 9, 10, 11, 12, 14, 15, 20, 30, 35, 60
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OFFSET
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1,2
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COMMENTS
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The maximum term of the n-th row is n*(n+1). The minimum term of the n-th row seems to be A063428(n) if n>=2. The length of row n is A146564(n) + 1.
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LINKS
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EXAMPLE
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The triangle begins:
1 2
1 2 3 4 6
2 3 4 6 12
2 3 4 5 6 8 12 20
4 5 6 10 30
2 3 4 5 6 7 8 9 10 12 15 18 24 42
6 7 8 14 56
...
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MAPLE
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for n from 1 to 10 do for m from 1 to n*(n+1) do if(n=m or m*n mod (m-n) = 0)then printf("%d, ", m): fi: od: od:
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CROSSREFS
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KEYWORD
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nonn,easy,tabf
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AUTHOR
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STATUS
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approved
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