A144220 Triangle read by rows, A118433 (the self-inverse triangle) * A000012^(-1).

1, 2, -1, -3, 1, 1, -4, 0, 4, -1, 5, 2, -10, 3, 1, 6, 5, -20, 5, 6, -1, -7, -9, 35, 5, -21, 5, 1, -8, -14, 56, 0, -56, 14, 8, -1, 9, 20, -84, -14, 126, -28, -36, 7, 1, 10, 27, -120, -42, 252, -42, -120, 27, 10, -1, -11, -35, 165, 90, -462, 42, 330, -75, -55, 9, 1

Offset

0,2

Comments

Row sums = (1, 1, -1, -1, 1, 1, ...).

Links

Table of n, a(n) for n=0..65.

Formula

A118433 * A000012^(-1), where A000012^(-1) is an infinite lower triangular matrix with 1's in the main diagonal and (-1)'s in the subdiagonal, with the rest zeros.

Example

First few rows of the triangle:
   1;
   2,  -1;
   3,   1,    1;
  -4,   0,    4,  -1
   5,   2,  -10,   3,   1;
   6,   5,  -20,   5,   6,  -1;
  -7,  -9,   35,  -5, -21,   5,    1;
  -8, -14,   56,   0, -56,  14,    8, -1;
   9,  20,  -84, -14, 126, -28,  -36,  7,  1;
  10,  27, -120, -42, 252, -42, -120, 27, 10, -1;
  ...

Crossrefs

Cf. A118433.

Sequence in context: A342724 A347046 A300322 * A156826 A130296 A126705

Adjacent sequences: A144217 A144218 A144219 * A144221 A144222 A144223

Keyword

tabl,sign

Author

Gary W. Adamson, Sep 14 2008

Status

approved