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A127475 Triangle T(n,k) read by rows: T(n,k) = mu(n)*phi(k) if k|n, else T(n,k)=0. 1
1, -1, -1, -1, 0, -2, 0, 0, 0, 0, -1, 0, 0, 0, -4, 1, 1, 2, 0, 0, 2, -1, 0, 0, 0, 0, 0, -6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 4, 0, 0, 0, 0, 4, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -12 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Table of n, a(n) for n=1..91.

FORMULA

T(n,k) = A054522(n,k)*A008683(n).

T(n,1) = A008683(n) = mu(n).

T(n,n) = A097945(n).

EXAMPLE

The triangle starts in row n=1 as:

1;

-1, -1;

-1, 0, -2;

0, 0, 0, 0;

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

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

-1, 0, 0, 0, 0, 0, -6;

...

CROSSREFS

Cf. A008683, A054522, A055615 (row sums), A097945, A023900.

Sequence in context: A089814 A063100 A294266 * A086014 A025437 A066032

Adjacent sequences:  A127472 A127473 A127474 * A127476 A127477 A127478

KEYWORD

tabl,easy,sign

AUTHOR

Gary W. Adamson, Jan 15 2007

STATUS

approved

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Last modified April 23 10:57 EDT 2021. Contains 343204 sequences. (Running on oeis4.)