A134248 M * A007318, M = a triangle by rows, n-th row = (n-1) zeros followed by T(n), 1.

1, 2, 1, 4, 5, 1, 7, 15, 9, 1, 11, 34, 36, 14, 1, 16, 65, 100, 70, 20, 1, 22, 111, 225, 230, 120, 27, 129, 175, 441, 595, 455, 189, 35, 1, 37, 260, 784, 1316, 1330, 812, 280, 44, 1, 46, 369, 1296, 2604, 3276, 2646, 1344, 396, 54, 1

Offset

0,2

Comments

Row sums = A104270: (1, 3, 10, 32, 96, 172, ...).

Left column = A000124.

Links

Table of n, a(n) for n=0..53.

Formula

M * A007318, where M = an infinite lower triangular matrix with rows: n-th row = (n-1) zeros followed by T(n), 1; T(n) = n-th triangular number. M = an infinite lower triangular matrix with (1,1,1,...) in the main diagonal and the triangular series in the subdiagonal.

Example

First few rows of the triangle:
   1;
   2,  1;
   4,  5,   1;
   7, 15,   9,  1;
  11, 34,  36, 14,  1;
  16, 65, 100, 70, 20, 1;
  ...

Crossrefs

Cf. A104270, A000124, A000217.

Sequence in context: A321000 A121289 A211561 * A248670 A080935 A362926

Adjacent sequences: A134245 A134246 A134247 * A134249 A134250 A134251

Keyword

nonn,tabl

Author

Gary W. Adamson, Oct 15 2007

Status

approved