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

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,  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