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A128187 Matrix product A128174 * A051731 read by rows. 3
1, 1, 1, 2, 0, 1, 2, 2, 0, 1, 3, 0, 1, 0, 1, 3, 3, 1, 1, 0, 1, 4, 0, 1, 0, 1, 0, 1, 4, 4, 1, 2, 0, 1, 0, 1, 5, 0, 2, 0, 1, 0, 1, 0, 1, 5, 5, 1, 2, 1, 1, 0, 1, 0, 1, 6, 0, 2, 0, 1, 0, 1, 0, 1, 0, 1, 6, 6, 2, 3, 1, 2, 0, 1, 0, 1, 0, 1, 7, 0, 2, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 7, 7, 2, 3, 1, 2, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..99.

FORMULA

A128174 * A051731 as infinite lower triangular matrices.

EXAMPLE

First few rows of the triangle are:

1;

1, 1;

2, 0, 1;

2, 2, 0, 1;

3, 0, 1, 0, 1;

3, 3, 1, 1, 0, 1;

4, 0, 1, 0, 1, 0, 1;

4, 4, 1, 2, 0, 1, 0, 1;

...

MAPLE

A128187 := proc(n, k)

    add( A128174(n, j)*A051731(j, k), j=k..n) ;

end proc: # R. J. Mathar, Apr 16 2013

CROSSREFS

Cf. A128188 (row sums), A128174, A051731.

Sequence in context: A062169 A113680 A316723 * A266477 A133121 A091602

Adjacent sequences:  A128184 A128185 A128186 * A128188 A128189 A128190

KEYWORD

nonn,easy,tabl

AUTHOR

Gary W. Adamson, Mar 07 2007

STATUS

approved

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Last modified October 16 21:10 EDT 2019. Contains 328103 sequences. (Running on oeis4.)