A127371 Triangle read by rows: A051731 * A054521, as infinite lower triangular matrices.

1, 2, 0, 2, 1, 0, 3, 0, 1, 0, 2, 1, 1, 1, 0, 4, 1, 0, 0, 1, 0, 2, 1, 1, 1, 1, 1, 0, 4, 0, 2, 0, 1, 0, 1, 0, 3, 2, 0, 1, 1, 0, 1, 1, 0, 4, 1, 2, 1, 0, 0, 1, 0, 1, 0, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 6, 1, 1, 0, 2, 0, 1, 0, 0, 0, 1, 0

Offset

1,2

Comments

Row sums = n, left column = d(n), (A000005: 1, 2, 2, 3, 2, 4, 2, ...).

Links

Table of n, a(n) for n=1..78.

Formula

Inverse Moebius transform of A054521.

Example

First few rows of the triangle:
  1;
  2, 0;
  2, 1, 0;
  3, 0, 1, 0;
  2, 1, 1, 1, 0;
  4, 1, 0, 0, 1, 0;
  2, 1, 1, 1, 1, 1, 0;
  4, 0, 2, 0, 1, 0, 1, 0;
  3, 2, 0, 1, 1, 0, 1, 1, 0;
  ...

Crossrefs

Cf. A000005, A051731, A054521.

Sequence in context: A190436 A133696 A195050 * A036849 A097364 A254204

Adjacent sequences: A127368 A127369 A127370 * A127372 A127373 A127374

Keyword

nonn,tabl

Author

Gary W. Adamson, Jan 12 2007

Extensions

Definition clarified, a(56) corrected and more terms from Georg Fischer, May 29 2023

Status

approved