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A129691 Inverse of A054523. 6
1, -1, 1, -2, 0, 1, -1, -1, 0, 1, -4, 0, 0, 0, 1, 2, -2, -1, 0, 0, 1, -6, 0, 0, 0, 0, 0, 1, -1, -1, 0, -1, 0, 0, 0, 1, -2, 0, -2, 0, 0, 0, 0, 0, 1, 4, -4, 0, 0, -1, 0, 0, 0, 0, 1, -10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, -1, -2, 0, -1, 0, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Row sums = A130054, (1, -1, -1, -3, 0, -5, -2, -3, 0,...). A129691 * A126988 = A051731. Left column = A023900: (1, -1, -2, -1, -4, 2, -6,...).

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..1275

FORMULA

A054523^(-1), as an infinite lower triangular matrix.

T(n,k) = A023900(n/k) for k | n, T(n,k) = 0 otherwise. - Andrew Howroyd, Aug 03 2018

EXAMPLE

First few rows of the triangle are:

1;

-1, 1;

-2, 0, 1;

-1, -1, 0, 1;

-4, 0, 0, 0, 1;

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

...

PROG

(PARI) T(n, k)={if(n%k, 0, sumdivmult(n/k, d, d*moebius(d)))} \\ Andrew Howroyd, Aug 03 2018

CROSSREFS

Cf. A054523, A130055, A023900, A126988, A051731.

Sequence in context: A278522 A024363 A050600 * A280750 A280748 A117454

Adjacent sequences:  A129688 A129689 A129690 * A129692 A129693 A129694

KEYWORD

tabl,sign

AUTHOR

Gary W. Adamson, May 04 2007

EXTENSIONS

Terms a(56) and beyond from Andrew Howroyd, Aug 03 2018

STATUS

approved

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Last modified April 20 08:50 EDT 2019. Contains 322306 sequences. (Running on oeis4.)