A133081 An interpolation operator, companion to A133080.

1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1

Offset

1,1

Comments

A133081 * [1,2,3,...] = A133090: (1, 1, 5, 3, 9, 5, 13, 7, 17, ...).

A133080: diagonal and subdiagonal are switched.

Links

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

Formula

Infinite lower triangular matrix, (1,0,1,0,...) in the main diagonal and (1,1,1,...) in the subdiagonal.

Example

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

Prog

(PARI) row(n) = vector(n, k, if (k==n-1, 1, if (k==n, n%2)));
lista(nn) = my(list=List()); for (n=1, nn, my(v=row(n)); for (k=1, #v, listput(list, v[k]))); Vec(list); \\ Michel Marcus, Mar 06 2022

Crossrefs

Cf. A133080, A133090, A040001 (row sums).

Sequence in context: A191747 A330323 A280933 * A352573 A285345 A125999

Adjacent sequences: A133078 A133079 A133080 * A133082 A133083 A133084

Keyword

nonn,easy,tabl

Author

Gary W. Adamson, Sep 09 2007

Extensions

More terms from Michel Marcus, Mar 06 2022

Status

approved