A128220 Triangle, A127701 * A000012.

1, 3, 2, 4, 4, 3, 5, 5, 5, 4, 6, 6, 6, 6, 5, 7, 7, 7, 7, 7, 6, 8, 8, 8, 8, 8, 8, 7, 9, 9, 9, 9, 9, 9, 9, 8, 10, 10, 10, 10, 10, 10, 10, 10, 9, 11, 11, 11, 11, 11, 11, 11, 11, 11, 10

Offset

1,2

Comments

Row sums = A028387: (1, 5, 11, 19, 29, 41, 55, ...) A000012 * A127701 = A128219.

Links

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

Formula

A127701 * A000012 as infinite lower triangular matrices. Triangle read by rows: a(1) = 1; n-th row = (n-1) terms of (n+1) followed by "n".

Example

First few rows of the triangle:
  1;
  3, 2;
  4, 4, 3;
  5, 5, 5, 4;
  6, 6, 6, 6, 5;
  7, 7, 7, 7, 7, 6;
  ...

Crossrefs

Cf. A128219, A000012, A127701, A028387.

Sequence in context: A023630 A110550 A236333 * A258242 A287869 A134749

Adjacent sequences: A128217 A128218 A128219 * A128221 A128222 A128223

Keyword

nonn,tabl

Author

Gary W. Adamson, Feb 19 2007

Status

approved