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A166240 Triangle read by rows, A000012 * A152140 as infinite lower triangular matrices. 1
1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 2, 1, 1, 1, 3, 2, 2, 1, 1, 1, 3, 4, 2, 2, 1, 1, 1, 4, 4, 4, 2, 2, 1, 1, 1, 1, 4, 6, 4, 4, 2, 2, 1, 1, 1, 5, 6, 7, 4, 4, 2, 2, 1, 1, 1, 5, 9, 7, 7, 4, 4, 2, 2, 1, 1, 1, 6, 9, 11, 7, 7, 4, 4, 2, 2, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,8

COMMENTS

Row sums = A036469, (partial sums of A000009).

The triangle = partial sums of A152140 starting from the top down, by columns.

LINKS

Table of n, a(n) for n=1..79.

FORMULA

Triangle read by rows, A000012 * A152140, where A000012 = an infinite lower triangular matrix with all 1's: [1; 1,1; 1,1,1;...].

EXAMPLE

First few rows of the triangle =

1;

1, 1;

1, 1, 1;

1, 2, 1, 1;

1, 2, 2, 1, 1;

1, 3, 2, 2, 1, 1;

1, 3, 4, 2, 2, 1, 1;

1, 4, 4, 4, 2, 2, 1, 1;

1, 4, 6, 4, 4, 2, 2, 1, 1;

1, 5, 6, 7, 4, 4, 2, 2, 1, 1;

1, 5, 9, 7, 7, 4, 4, 2, 2, 1, 1;

1, 6, 9, 11, 7, 7, 4, 4, 2, 2, 1, 1;

1, 6, 12, 11, 12, 7, 7, 4, 4, 2, 2, 1, 1;

1, 7, 12, 16, 12, 12, 7, 7, 4, 4, 2, 2, 1, 1;

1, 7, 16, 16, 18, 12, 12, 7, 7, 4, 4, 2, 2, 1, 1;

1, 8, 16, 23, 18, 19, 12, 19, 7, 7, 4, 4, 2, 2, 1, 1;

...

CROSSREFS

A152140, A036469, A000009

Sequence in context: A284249 A137350 A334607 * A219347 A114087 A215521

Adjacent sequences:  A166237 A166238 A166239 * A166241 A166242 A166243

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Oct 09 2009

STATUS

approved

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Last modified July 30 15:29 EDT 2021. Contains 346359 sequences. (Running on oeis4.)