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A182728
Array T(n,k) = n*k*A000041(n) read by antidiagonals, n,k >= 1.
4
1, 4, 2, 9, 8, 3, 20, 18, 12, 4, 35, 40, 27, 16, 5, 66, 70, 60, 36, 20, 6, 105, 132, 105, 80, 45, 24, 7, 176, 210, 198, 140, 100, 54, 28, 8, 270, 352, 315, 264, 175, 120, 63, 32, 9, 420, 540, 528, 420, 330, 210, 140, 72, 36, 10, 616, 840, 810, 704, 525, 396, 245, 160, 81, 40, 11
OFFSET
1,2
EXAMPLE
Array begins:
1, 2, 3, 4, 5, 6, 7, ...
4, 8, 12, 16, 20, 24, 28, ...
9, 18, 27, 36, 45, 54, 63, ...
20, 40, 60, 80, 100, 120, 140, ...
35, 70, 105, 140, 175, 210, 245, ...
66, 132, 198, 264, 330, 396, 462, ...
105, 210, 315, 420, 525, 630, 735, ...
MAPLE
A182728 := proc(n, k) n*k*combinat[numbpart](n) ; end proc:
seq(seq( A182728(d+1-k, k), k=1..d), d=1..10) ; # R. J. Mathar, Feb 01 2011
CROSSREFS
Column 1 gives A066186. Column 24 gives A183009.
Sequence in context: A104583 A278103 A249327 * A290538 A097664 A144811
KEYWORD
nonn,easy,tabl
AUTHOR
Omar E. Pol, Jan 22 2011
STATUS
approved