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A348649
Odd numbers in the triangle of Stirling numbers of the second kind (A008277).
2
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
OFFSET
1,5
COMMENTS
We take the odd values in A008277, as they appear, with duplicates.
For any n >= 1, the n-th row has A007306(n) terms.
EXAMPLE
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;
...
PROG
(PARI) row(n) = select(v -> v%2==1, vector(n, k, stirling(n, k, 2)))
CROSSREFS
See A014421, A014428, A014450, A014459 for similar sequences.
Cf. A007306, A008277, A348650 (even numbers).
Sequence in context: A102479 A228902 A053193 * A010273 A046143 A228035
KEYWORD
nonn,tabf
AUTHOR
Rémy Sigrist, Oct 27 2021
STATUS
approved