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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
OFFSET
1,3
COMMENTS
A130207 replaces sigma(n) with phi(n), A000010. A130209 replaces sigma(n) with d(n), A000005.
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
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, May 16 2007
STATUS
approved