A106478 - OEIS

A106478

Inverse of sequence array for Euler phi function.

1, -1, 1, -1, -1, 1, 1, -1, -1, 1, -1, 1, -1, -1, 1, 3, -1, 1, -1, -1, 1, -3, 3, -1, 1, -1, -1, 1, -1, -3, 3, -1, 1, -1, -1, 1, 7, -1, -3, 3, -1, 1, -1, -1, 1, -9, 7, -1, -3, 3, -1, 1, -1, -1, 1, 5, -9, 7, -1, -3, 3, -1, 1, -1, -1, 1, -1, 5, -9, 7, -1, -3, 3, -1, 1, -1, -1, 1, -7, -1, 5, -9, 7, -1, -3, 3, -1, 1, -1, -1, 1, 25, -7, -1, 5, -9, 7, -1

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OFFSET

0,16

COMMENTS

Row sums are A106480. Sequence matrix for A106479.

LINKS

Table of n, a(n) for n=0..97.

FORMULA

Riordan array (1/Sum_{j>=0, phi(j+1) x^j}, x).

EXAMPLE

Triangle begins:

-1, 1;

1, -1, -1, 1;

-1, 1, -1, -1, 1;

3, -1, 1, -1, -1, 1;

-3, 3, -1, 1, -1, -1, 1;

-1, -3, 3, -1, 1, -1, -1, 1;

...

CROSSREFS

Cf. A000010 (phi), A106479, A106480.

Sequence in context: A124385 A317624 A328575 * A115069 A046556 A046535

Adjacent sequences: A106475 A106476 A106477 * A106479 A106480 A106481

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry, May 03 2005

STATUS

approved