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A130209 Diagonalized matrix of d(n), A000005. 8
1, 0, 2, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..93.

FORMULA

T(n,n) = A000005(n),

T(n,k) = 0 if n <> k.

EXAMPLE

First few rows of the triangle are:

1;

0, 2;

0, 0, 2;

0, 0, 0, 3;

0, 0, 0, 0, 2;

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

...

MAPLE

A130209 := proc(n, k)

    if k = n then

        numtheory[tau](n);

    else

        0;

    end if;

end proc: # R. J. Mathar, Aug 06 2016

CROSSREFS

Cf. A000005, A130207, A130209.

Sequence in context: A242609 A226225 A329265 * A109127 A263456 A002284

Adjacent sequences:  A130206 A130207 A130208 * A130210 A130211 A130212

KEYWORD

nonn,tabl,easy

AUTHOR

Gary W. Adamson, May 16 2007

STATUS

approved

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Last modified December 5 10:45 EST 2019. Contains 329751 sequences. (Running on oeis4.)