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A154558 Triangle read by rows, A007318 * (A001006 * 0^(n-k)) 1
1, 1, 2, 1, 4, 4, 1, 6, 12, 9, 1, 8, 24, 36, 21, 1, 10, 40, 90, 105, 51, 1, 12, 60, 180, 315, 306, 127, 1, 14, 84, 315, 735, 1071, 889, 323, 1, 16, 112, 504, 1470, 2856, 3556, 2584, 835, 1, 18, 144, 756, 2646, 6426, 10668, 11628, 7515, 2188 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Row sums = A000245 starting with offset 1: (1, 3, 9, 28, 90, 297,...).

Right border = A001006 starting with offset 1.

LINKS

Table of n, a(n) for n=1..55.

FORMULA

Binomial transform of a diagonalized version of the Motzkin sequence:

(A001006 (1, 2, 4, 9, 21, 51,...) as the main diagonal and the rest zeros.)

EXAMPLE

First few rows of the triangle =

1;

1, 2;

1, 4, 4;

1, 6, 12, 9;

1, 8, 24, 36, 21;

1, 10, 40, 90, 105, 51;

1, 12, 60, 180, 315, 306, 127;

1, 14, 84, 315, 735, 1071, 889, 323;

1, 16, 112, 504, 1470, 2856, 3556, 2584, 835;

1, 18, 144, 756, 2646, 6426, 10668, 11628, 7515, 2188;

1, 20, 180, 1080, 4410, 12852, 26670, 38760, 37575, 21880, 5798;

...

CROSSREFS

Cf. A001006, A000245

Sequence in context: A097750 A133544 A013609 * A220836 A008572 A209150

Adjacent sequences:  A154555 A154556 A154557 * A154559 A154560 A154561

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Jan 11 2009

STATUS

approved

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Last modified February 23 13:05 EST 2018. Contains 299581 sequences. (Running on oeis4.)