A127733 Triangle read by rows: n-th row is n^2 preceded by (n-1) zeros.

1, 0, 4, 0, 0, 9, 0, 0, 0, 16, 0, 0, 0, 0, 25, 0, 0, 0, 0, 0, 36, 0, 0, 0, 0, 0, 0, 49, 0, 0, 0, 0, 0, 0, 0, 64, 0, 0, 0, 0, 0, 0, 0, 0, 81, 0, 0, 0, 0, 0, 0, 0, 0, 0, 100, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 121, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 144, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 169

Offset

1,3

Links

Andrew Howroyd, Table of n, a(n) for n = 1..1275 (first 50 rows)

Formula

T(n,k) = A127648(n-1,k-1)^2.

T(n,k) = 0 for k < n.

Example

First few rows of the triangle are:
  1;
  0, 4;
  0, 0, 9;
  0, 0, 0, 16;
  0, 0, 0,  0, 25;
  ...

Prog

(PARI) T(n, k) = if(n==k, n^2, 0) \\ Andrew Howroyd, Sep 20 2025

Crossrefs

Row sums and main diagonal are A000290.

Cf. A127648.

Sequence in context: A048728 A391586 A002915 * A330379 A364102 A249035

Adjacent sequences: A127730 A127731 A127732 * A127734 A127735 A127736

Keyword

nonn,tabl

Author

Gary W. Adamson, Jan 26 2007

Extensions

a(29) onwards from Andrew Howroyd, Sep 20 2025

Status

approved