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A127471 Triangle, row sums = sigma(n), left column = d(n), right border = phi(n). 1
1, 2, 1, 2, 0, 2, 3, 2, 0, 2, 2, 0, 0, 0, 4, 4, 2, 4, 0, 0, 2, 2, 0, 0, 0, 0, 0, 6, 4, 3, 0, 4, 0, 0, 0, 4, 3, 0, 4, 0, 0, 0, 0, 0, 6, 4, 2, 0, 8, 0, 0, 0, 0, 4 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Left column (1, 2, 2, 3, 2, 4,...) = d(n)A000005; right border (1, 1, 2, 2, 4, 2, 6,...) = phi(n), A000010; row sums, (1, 3, 4, 7, 6, 12,...) = sigma(n), A000203.

FORMULA

Inverse Mobius transform of A054522; (A051731 * A054522 as infinite lower triangular matrices).

EXAMPLE

First few rows of the triangle are:

1;

2, 1;

2, 0, 2;

3, 2, 0, 2;

2, 0, 0, 0, 4;

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

2, 0, 0, 0, 0, 0, 6;

4, 3, 0, 4, 0, 0, 0, 4;

3, 0, 4, 0, 0, 0, 0, 0, 6;

4, 2, 0, 0, 8, 0, 0, 0, 0, 4;

...

CROSSREFS

Cf. A054522, A051731, A000005, A000203, A000010.

Sequence in context: A046144 A144736 A137423 * A071485 A127969 A081733

Adjacent sequences:  A127468 A127469 A127470 * A127472 A127473 A127474

KEYWORD

nonn,tabl,uned

AUTHOR

Gary W. Adamson (qntmpkt(AT)yahoo.com), Jan 15 2007

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Last modified February 13 17:43 EST 2012. Contains 205523 sequences.