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A137587 Triangle read by rows: A051731 * A026794. 2
1, 2, 1, 3, 0, 1, 5, 2, 0, 1, 6, 1, 0, 0, 1, 11, 3, 2, 0, 0, 1, 12, 2, 1, 0, 0, 0, 1, 20, 6, 1, 2, 0, 0, 0, 1, 25, 4, 3, 1, 0, 0, 0, 0, 1, 37, 9, 2, 1, 2, 0, 0, 0, 0, 1, 43, 8, 3, 1, 1, 0, 0, 0, 0, 0, 1, 70, 16, 6, 3, 1, 2, 0, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

That is, regard A051731 and A026794 as lower triangular square matrices and multiply them, then take the lower triangle of the product,

Left column = A083710 starting (1, 2, 3, 5, 6, 11, 12,...). Row sums = A047968.

LINKS

Table of n, a(n) for n=1..78.

FORMULA

Inverse mobius transform of the partition triangle, A026794

EXAMPLE

First few rows of the triangle are:

.1;

.2, 1;

.3, 0, 1;

.5, 2, 0, 1;

.6, 1, 0, 0, 1;

.11, 3, 2, 0, 0, 1;

.12, 2, 1, 0, 0, 0, 1;

.20, 6, 1, 2, 0, 0, 0, 1;

.25, 4, 3, 1, 0, 0, 0, 0, 1;

....

CROSSREFS

Cf. A026794, A051731, A083710, A047968.

Sequence in context: A195665 A096798 A158902 * A168021 A137639 A239631

Adjacent sequences:  A137584 A137585 A137586 * A137588 A137589 A137590

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Jan 27 2008

EXTENSIONS

Typo in 9th row corrected by M. F. Hasler, Jun 08 2009

STATUS

approved

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Last modified August 18 17:58 EDT 2017. Contains 290732 sequences.