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A348650
Even numbers in the triangle of Stirling numbers of the second kind (A008277).
2
6, 10, 90, 350, 140, 966, 1050, 266, 28, 7770, 2646, 462, 36, 9330, 5880, 750, 145750, 246730, 11880, 86526, 1379400, 1323652, 627396, 66, 2532530, 9321312, 5715424, 1899612, 359502, 78, 788970, 49329280, 20912320, 5135130, 752752, 66066, 42355950, 210766920
OFFSET
4,1
COMMENTS
We take the even values in A008277, as they appear, with duplicates.
For any n >= 4, the n-th row has n - A007306(n) terms.
EXAMPLE
As an irregular table, the first rows are:
4: 6;
5: 10;
6: 90;
7: 350, 140;
8: 966, 1050, 266, 28;
9: 7770, 2646, 462, 36;
10: 9330, 5880, 750;
11: 145750, 246730, 11880;
12: 86526, 1379400, 1323652, 627396, 66;
13: 2532530, 9321312, 5715424, 1899612, 359502, 78;
14: 788970, 49329280, 20912320, 5135130, 752752, 66066;
...
PROG
(PARI) row(n) = select(v -> v%2==0, vector(n, k, stirling(n, k, 2)))
CROSSREFS
Cf. A007306, A008277, A348649 (odd numbers).
Sequence in context: A256246 A246800 A269341 * A201921 A117310 A174322
KEYWORD
nonn,look,tabf
AUTHOR
Rémy Sigrist, Oct 27 2021
STATUS
approved