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A159974 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. 1
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 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

2,4

COMMENTS

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,...).

LINKS

Table of n, a(n) for n=2..67.

FORMULA

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

EXAMPLE

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).

CROSSREFS

Cf. A034943

Sequence in context: A172366 A132148 A237829 * A143866 A155002 A182413

Adjacent sequences:  A159971 A159972 A159973 * A159975 A159976 A159977

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Apr 28 2009

STATUS

approved

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Last modified November 21 06:00 EST 2019. Contains 329350 sequences. (Running on oeis4.)