2,4

Row sums = A034943 starting (1, 2, 5, 12, 28, 65, 151, 351,...).

As a property of eigentriangles, sum of n-th row terms = rightmost term of next row.

A034943 starting (1, 2, 5, 12, 28,...) = the INVERT transform of (1, 1, 2, 3, 4, 5,...).

Triangle read by rows, M * Q.; M = an infinite lower triangular Toeplitz matrix with (1, 1, 2, 3, 4, 5,...) in every column. Q = a matrix with A034943: (1, 1, 2, 5, 12, 28,...) as the main diagonal and the rest zeros

First few rows of the triangle =

1;

1, 1;

2, 1, 2;

3, 2, 2, 5;

4, 3, 4, 5, 12;

5, 4, 6, 10, 12, 28;

6, 5, 8, 15, 24, 28, 65;

7, 6, 10, 20, 36, 56, 65, 151;

8, 7, 12, 25, 48, 84, 130, 151, 351;

9, 8, 14, 30, 60, 112, 195, 302, 351, 816;

10, 9, 16, 35, 72, 140, 260, 453, 702, 816, 1897;

...

Example: row 6 = (4, 3, 4, 5, 12) = termwise products of (1, 1, 2, 5, 12)

and (4, 3, 2, 1, 1).

Cf. A034943

Sequence in context: A111725 A112218 A132148 this_sequence A143866 A155002 A103342

Adjacent sequences: A159971 A159972 A159973 this_sequence A159975 A159976 A159977

nonn,tabl

Gary W. Adamson (qntmpkt(AT)yahoo.com), Apr 28 2009