A129264 Triangle read by rows: A000012 * A115361 as infinite lower triangular matrices.

1, 2, 1, 2, 1, 1, 3, 2, 1, 1, 3, 2, 1, 1, 1, 3, 2, 2, 1, 1, 1, 3, 2, 2, 1, 1, 1, 1, 4, 3, 2, 2, 1, 1, 1, 1, 4, 3, 2, 2, 1, 1, 1, 1, 1, 4, 3, 2, 2, 2, 1, 1, 1, 1, 1, 4, 3, 2, 2, 2, 1, 1, 1, 1, 1, 1, 4, 3, 3, 2, 2, 2, 1, 1, 1, 1, 1, 1

Offset

1,2

Comments

Triangle read by rows, A000012 * A115361; where A000012 = an infinite lower triangular matrix with all 1's: [1; 1,1; 1,1,1; ...] and A115361 = the ruler function triangle.

The operation A000012 * A115361 takes partial sums of A115361 column terms starting from the top. [Gary W. Adamson, Nov 27 2009]

Eigensequence of the triangle = A089067: (1, 3, 5, 13, 23, 51, 97, 207, ...). [Gary W. Adamson, Nov 27 2009]

Row sums = A005187: (1, 3, 4, 7, 8, 10, 11, 15, ...).

Left column = A070939 starting (1, 2, 2, 3, 3, 3, 3, 4, 4, 4, ...).

Links

Table of n, a(n) for n=1..78.

Example

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

Crossrefs

Cf. A000012, A005187, A070939, A089067, A115361, A129265.

Sequence in context: A323345 A135539 A240060 * A135840 A228570 A173305

Adjacent sequences: A129261 A129262 A129263 * A129265 A129266 A129267

Keyword

nonn,tabl

Author

Gary W. Adamson, Apr 06 2007

Extensions

Incorrect a(79) removed by Georg Fischer, Jul 04 2023

Status

approved