A131088 2*A051731 - A054525 as infinite lower triangular matrices.

1, 3, 1, 3, 0, 1, 2, 3, 0, 1, 3, 0, 0, 0, 1, 1, 3, 3, 0, 0, 1, 3, 0, 0, 0, 0, 0, 1, 2, 2, 0, 3, 0, 0, 0, 1, 2, 0, 3, 0, 0, 0, 0, 0, 1, 1, 3, 0, 0, 3, 0, 0, 0, 0, 1, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 1, 2, 3, 0, 3, 0, 0, 0, 0, 0, 1, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1

Offset

1,2

Comments

Row sums = A131089.

A131090: (1, 3, 3, 2, 3, 1, 3, 2, 2, 1, ...) in every column interspersed with (k-1) zeros.

Links

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

Example

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

Prog

(PARI) T(n, k) = 2*!(n%k) - if (!(n % k), moebius(n/k), 0);
row(n) = vector(n, k, T(n, k));
lista(nn) = for (n=1, nn, v = row(n); for (k=1, #v, print1(v[k], ", "))); \\ Michel Marcus, Feb 26 2022

Crossrefs

Cf. A129979 (left border), A131089 (row sums), A051731, A054525.

Sequence in context: A179656 A167274 A201679 * A136157 A266260 A143353

Adjacent sequences: A131085 A131086 A131087 * A131089 A131090 A131091

Keyword

nonn,tabl

Author

Gary W. Adamson, Jun 14 2007

Extensions

More terms from Michel Marcus, Feb 26 2022

Status

approved