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A348649
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Odd numbers in the triangle of Stirling numbers of the second kind (A008277).
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2
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1, 1, 1, 1, 3, 1, 1, 7, 1, 1, 15, 25, 1, 1, 31, 65, 15, 1, 1, 63, 301, 21, 1, 1, 127, 1701, 1, 1, 255, 3025, 6951, 1, 1, 511, 34105, 42525, 22827, 45, 1, 1, 1023, 28501, 179487, 63987, 1155, 55, 1, 1, 2047, 611501, 159027, 22275, 1705, 1, 1, 4095, 261625, 7508501, 39325, 2431, 1
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OFFSET
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1,5
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COMMENTS
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We take the odd values in A008277, as they appear, with duplicates.
For any n >= 1, the n-th row has A007306(n) terms.
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LINKS
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EXAMPLE
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As an irregular table, the first rows are:
1: 1;
2: 1, 1;
3: 1, 3, 1;
4: 1, 7, 1;
5: 1, 15, 25, 1;
6: 1, 31, 65, 15, 1;
7: 1, 63, 301, 21, 1;
8: 1, 127, 1701, 1;
9: 1, 255, 3025, 6951, 1;
10: 1, 511, 34105, 42525, 22827, 45, 1;
11: 1, 1023, 28501, 179487, 63987, 1155, 55, 1;
...
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PROG
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(PARI) row(n) = select(v -> v%2==1, vector(n, k, stirling(n, k, 2)))
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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STATUS
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approved
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