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A185785 Second accumulation array of A107985, by antidiagonals. 3
1, 5, 5, 15, 24, 15, 35, 70, 70, 35, 70, 160, 200, 160, 70, 126, 315, 450, 450, 315, 126, 210, 560, 875, 1000, 875, 560, 210, 330, 924, 1540, 1925, 1925, 1540, 924, 330, 495, 1440, 2520, 3360, 3675, 3360, 2520, 1440, 495, 715, 2145, 3900, 5460, 6370, 6370, 5460, 3900, 2145, 715, 1001, 3080, 5775, 8400, 10290, 10976, 10290, 8400, 5775, 3080, 1001 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See A185784.

LINKS

G. C. Greubel, Table of n, a(n) for the first 50 rows, flattened

FORMULA

T(n,k) = (n+k+2)*C(n+2,3)*C(k+2,3)/4, k>=1, n>=1.

EXAMPLE

Northwest corner:

1....5....15....35....70

5....24...70....160...315

15...70...200...450...875

35...160..450...1000..1925

MATHEMATICA

f[n_, k_] := Binomial[k + 2, 3]*Binomial[n + 2, 3]*(n + k + 2)/4;

Table[f[n - k + 1, k], {n, 50}, {k, n, 1, -1}] // Flatten (* G. C. Greubel, Jul 12 2017 *)

CROSSREFS

Cf. A185784.

Sequence in context: A188272 A104551 A100746 * A185905 A050341 A140360

Adjacent sequences:  A185782 A185783 A185784 * A185786 A185787 A185788

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Feb 03 2011

STATUS

approved

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Last modified February 18 20:04 EST 2019. Contains 320262 sequences. (Running on oeis4.)