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A178238 Triangle read by rows, A000012 * triangle A000027. 1
1, 3, 3, 7, 8, 6, 14, 16, 15, 10, 25, 28, 28, 24, 15, 41, 45, 46, 43, 35, 21, 63, 68, 70, 68, 61, 48, 28, 92, 98, 101, 100, 94, 82, 63, 36, 129, 136, 140, 140, 135, 124, 106, 80, 45, 175, 183, 188, 189, 185, 175, 158, 133, 99, 55 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row sums = A002817: (1, 6, 21, 55, 120,...).

LINKS

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

FORMULA

A000012 * A000027 as infinite lower triangular matrices; where A000012 = the

all 1's triangle and A000027 = the natural number triangle [1; 2,3; 4,5,6;...]. The operation takes partial sums of the natural number triangle terms by columns.

EXAMPLE

First few rows of the triangle =

1;

3, 3;

7, 8, 6;

14, 16, 15, 10;

25, 28, 28, 24, 15;

41, 45, 46, 43, 35, 21;

63, 68, 70, 68, 61, 48, 28;

92, 98, 101, 100, 94, 82, 63, 36;

129, 136, 140, 140, 135, 124, 106, 80, 45;

175, 183, 188, 189, 185, 175, 158, 133, 99, 55;

231, 240, 246, 248, 245, 236, 220, 196, 163, 120, 66;

298, 308, 314, 318, 316, 308, 293, 270, 238, 196, 143, 78;

377, 388, 395, 400, 399, 392, 378, 356, 325, 284, 232, 168, 91;

469, 481, 489, 495, 495, 489, 476, 455, 425, 385, 334, 271, 195, 105;

575, 588, 397, 604, 605, 600, 588, 568, 539, 500, 450, 388, 313, 224, 120;

...

CROSSREFS

Cf. A002817, A000027

Sequence in context: A021300 A121527 A021886 * A255333 A200792 A218567

Adjacent sequences:  A178235 A178236 A178237 * A178239 A178240 A178241

KEYWORD

easy,nonn,tabl

AUTHOR

Gary W. Adamson, May 23 2010

STATUS

approved

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Last modified April 10 16:05 EDT 2021. Contains 342845 sequences. (Running on oeis4.)