A128136 A128132 * A002260.

1, 1, 4, 2, 4, 9, 3, 6, 9, 16, 4, 8, 12, 16, 25, 5, 10, 15, 20, 25, 36, 6, 12, 18, 24, 30, 36, 49, 7, 14, 21, 28, 35, 42, 49, 64, 8, 16, 24, 32, 40, 48, 56, 64, 81, 9, 18, 27, 36, 45, 54, 63, 72, 81, 100

Offset

1,3

Comments

Row sums = A006003: (1, 5, 15, 34, 65, ...).

A002260 * A128132 = A128137.

Links

Table of n, a(n) for n=1..55.

Formula

A128132 * A002260 as infinite lower triangular matrices.

Example

First few rows of the triangle:
  1;
  1,  4;
  2,  4,  9;
  3,  6,  9, 16;
  4,  8, 12, 16, 25;
  5, 10, 15, 20, 25, 36;
  6, 12, 18, 24, 30, 36, 49;
  ...

Crossrefs

Cf. A128132, A002260, A006003, A128137.

Sequence in context: A345413 A137718 A007361 * A048147 A203001 A051666

Adjacent sequences: A128133 A128134 A128135 * A128137 A128138 A128139

Keyword

nonn,tabl

Author

Gary W. Adamson, Feb 16 2007

Status

approved