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A130208 Diagonalized matrix of A000203, Sigma(n). 5
1, 0, 3, 0, 0, 4, 0, 0, 0, 7, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 12, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 15 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

A130207 replaces Sigma(n) with phi(n), A000010. A130209 replaces Sigma(n) with d(n), A000005.

LINKS

Table of n, a(n) for n=1..36.

FORMULA

Infinite lower triangular matrix with A000203, Sigma(n), in the main diagonal and the rest zeros.

EXAMPLE

First few rows of the triangle are:

1;

0, 3;

0, 0, 4;

0, 0, 0, 7;

0, 0, 0, 0, 6;

0, 0, 0, 0, 0, 12;

...

PROG

(PARI) for(n=1, 9, for(k=2, n, print1("0, ")); print1(sigma(n)", ")) \\ Charles R Greathouse IV, Feb 14 2013

CROSSREFS

Cf. A000203, A130207, A130209.

Sequence in context: A021773 A244126 A133109 * A288654 A259191 A240455

Adjacent sequences:  A130205 A130206 A130207 * A130209 A130210 A130211

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, May 16 2007

STATUS

approved

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Last modified January 17 14:12 EST 2019. Contains 319225 sequences. (Running on oeis4.)