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A127449
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Triangle T(n,k) = n if gcd(n,k)=1, =0 otherwise.
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0
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1, 2, 0, 3, 3, 0, 4, 0, 4, 0, 5, 5, 5, 5, 0, 6, 0, 0, 0, 6, 0, 7, 7, 7, 7, 7, 7, 0, 8, 0, 8, 0, 8, 0, 8, 0, 9, 9, 0, 9, 9, 0, 9, 9, 0, 10, 0, 10, 0, 0, 0, 10, 0, 10, 0
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| T(n,k) = n *A054521(n,k), 1<=k<=n.
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EXAMPLE
| First few rows of the triangle are:
1;
2, 0;
3, 3, 0;
4, 0, 4, 0;
5, 5, 5, 5, 0;
6, 0, 0, 0, 6, 0;
7, 7, 7, 7, 7, 7, 0;
...
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CROSSREFS
| Cf. A002618 (row sums), A054521.
Sequence in context: A004557 A088276 A099838 * A138057 A053727 A127952
Adjacent sequences: A127446 A127447 A127448 * A127450 A127451 A127452
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KEYWORD
| nonn,tabl,easy
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AUTHOR
| Gary W. Adamson (qntmpkt(AT)yahoo.com), Jan 14 2007
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