

A180264


Triangle, row sums = A006054; derived from an infinite lower triangular matrix with (1,1,1,...) as the leftmost column and (1,2,1,1,1,...) as other columns.


2



1, 1, 1, 2, 2, 1, 1, 1, 4, 5, 1, 1, 2, 10, 11, 1, 1, 2, 5, 22, 25, 1, 1, 2, 5, 11, 50, 56, 1, 1, 2, 5, 11, 50, 56, 1, 1, 2, 5, 11, 25, 112, 126, 1, 1, 2, 5, 11, 25, 56, 252, 283, 1, 1, 2, 5, 11, 25, 56, 126, 566, 636, 1, 1, 2, 5, 11, 25, 56, 126, 283, 1272, 1429
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OFFSET

1,4


COMMENTS

Row sums = A006054 starting (1, 2, 5, 11, 25, 56, 126,...).
Sum of nth row terms = rightmost term of next row.


LINKS

Table of n, a(n) for n=1..73.


FORMULA

Let M = an infinite lower triangular matrix with 1's in the leftmost column,
and (1,2,1,1,1,...) as other columns. Let Q = a diagonalized variant of
A006054 (1, 1, 2, 5, 11, 25, 56,...) as the right border and the rest zeros.
Triangle A180264 = M*Q.


EXAMPLE

First few rows of the triangle =
.
1;
1, 1;
1, 2, 2;
1, 1, 4, 5;
1, 1, 2, 10, 11;
1, 1, 2, 5, 22, 25;
1, 1, 2, 5, 11, 50, 56;
1, 1, 2, 5, 11, 25, 112, 126;
1, 1, 2, 5, 11, 25, 56, 252, 283;
1, 1, 2, 5, 11, 25, 56, 126, 566, 636;
1, 1, 2, 5, 11, 25, 56, 126, 283, 1272, 1429;
1, 1, 2, 5, 11, 25, 56, 126, 283, 636, 2858, 3211;
...
Example: Row 4 = (1, 1, 4, 5) = termwise products of (1, 1, 2, 1) and (1, 1, 2, 5).


CROSSREFS

Cf. A006054
Sequence in context: A104320 A340142 A242618 * A225200 A128706 A253586
Adjacent sequences: A180261 A180262 A180263 * A180265 A180266 A180267


KEYWORD

nonn,tabf


AUTHOR

Gary W. Adamson, Aug 21 2010


STATUS

approved



