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A248846
Triangle read by rows: T(m,n) = number of ways of distributing n distinguishable balls into m distinguishable bins of size 4 where empty bins are permitted (m >= 1, 1 <= n <= 4m).
0
1, 1, 1, 1, 2, 4, 8, 16, 30, 50, 70, 70, 3, 9, 27, 81, 240, 690, 1890, 4830, 11130, 22050, 34650, 34650, 4, 16, 64, 256, 1020, 4020, 15540, 58380, 210840, 722400, 2310000, 6745200, 17417400, 37837800, 63063000, 63063000, 5, 25, 125, 625, 3120, 15500, 76300, 370300, 1761900, 8166900, 36613500, 157426500, 642642000, 2459457000
OFFSET
1,5
FORMULA
E.g.f. for row m: (sum(k=0..s) z^k/k!)^m, s=4.
EXAMPLE
Triangle T(n, m) is
1, 1, 1, 1;
2, 4, 8, 16, 30, 50, 70, 70;
3, 9, 27, 81, 240, 690, 1890, 4830, 11130, 22050, 34650, 34650;
4, 16, 64, 256, 1020, 4020, 15540,58380, 210840, 722400, 2310000, 6745200, 17417400, 37837800, 63063000, 63063000;
MAPLE
P := proc(n, m, s) n!*coeftayl(add(z^k/k!, k=0..s)^m, z=0, n); end;
CROSSREFS
Sequence in context: A332835 A018469 A098904 * A046127 A271480 A226454
KEYWORD
nonn,tabf
AUTHOR
Marko Riedel, Oct 15 2014
STATUS
approved