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A135853 A103516 * A007318 as an infinite lower triangular matrix. 3
1, 4, 2, 6, 6, 3, 8, 12, 12, 4, 10, 20, 30, 20, 5, 12, 30, 60, 60, 30, 6, 14, 42, 105, 140, 105, 42, 7, 16, 56, 168, 280, 280, 168, 56, 8, 18, 72, 252, 504, 630, 504, 252, 72, 9, 20, 90, 360, 840, 1260, 1260, 840, 360, 90, 10 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

FORMULA

A135852 = A007318 * A103516.

T(n, n) = n, T(n, 1) = 2*n, T(n, k) = k*binomial(n, k). - G. C. Greubel, Dec 07 2016

EXAMPLE

First few rows of the triangle are:

   1;

   4,   2;

   6,   6,  3;

   8,  12,  12,   4;

  10,  20,  30,  20,   5;

  12,  30,  60,  60,  30,   6;

  14,  42, 105, 140, 105,  42,   7;

  ...

MATHEMATICA

T[n_, n_] := n; T[n_, 1] := 2*n; T[n_, k_] := k*Binomial[n, k]; Table[T[n, k], {n, 1, 25}, {k, 1, n}]//flatten (* G. C. Greubel, Dec 07 2016 *)

CROSSREFS

Cf. A103516, A135854 (row sums), A135852.

Sequence in context: A228084 A188941 A200347 * A173197 A256568 A138947

Adjacent sequences:  A135850 A135851 A135852 * A135854 A135855 A135856

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Dec 01 2007

STATUS

approved

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Last modified September 21 02:46 EDT 2020. Contains 337266 sequences. (Running on oeis4.)