A137593 Triangle read by rows: matrix product A000012 * A136717.

1, 1, 2, 1, 4, 4, 1, 4, 16, 12, 1, 4, 16, 84, 48, 1, 4, 16, 156, 504, 192, 1, 4, 16, 156, 1464, 3312, 960, 1, 4, 16, 156, 1464, 14112, 24720, 5760, 1, 4, 16, 156, 1464, 24912, 158640, 189360, 34560, 1, 4, 16, 156, 1464, 24912, 400560, 1761840, 1607040, 241920

Offset

1,3

Comments

Right border = A004527: (1, 2, 4, 12, 48, 192, ...).

Row sums = A007489 starting (1, 3, 9, 33, 153, ...).

Links

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

Formula

A000012 * A136717 as infinite lower triangular matrices.

Example

First few rows of the triangle:
  1;
  1, 2;
  1, 4,  4;
  1, 4, 16,  12;
  1, 4, 16,  84,   48;
  1, 4, 16, 156,  504,  192;
  1, 4, 16, 156, 1464, 3312, 960;
  ...

Crossrefs

Cf. A136717, A004527, A007489.

Sequence in context: A274980 A274826 A129862 * A009949 A070785 A214985

Adjacent sequences: A137590 A137591 A137592 * A137594 A137595 A137596

Keyword

nonn,tabl

Author

Gary W. Adamson, Jan 28 2008

Extensions

Typo in eighth row corrected by Olivier Gérard, Oct 30 2012

Status

approved