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A135152 A004736 + A128174 - I, I = Identity matrix. 2
1, 2, 1, 4, 2, 1, 4, 4, 2, 1, 6, 4, 4, 2, 1, 6, 6, 4, 4, 2, 1, 8, 6, 6, 4, 4, 2, 1, 8, 8, 6, 6, 4, 4, 2, 1, 10, 8, 8, 6, 6, 4, 4, 2, 1, 10, 10, 8, 8, 6, 6, 4, 4, 2, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row sums = A047838: (1, 3, 7, 11, 17, 23, 31, 39,...). The triangle is a companion to A135151.

LINKS

Table of n, a(n) for n=1..55.

FORMULA

A004736 + A128174 - I, where I = Identity matrix, A004736 = (1; 2,1; 3,2,1;...) and A128174 = (1; 0,1; 1,0,1; 0,1,0,1;...).

EXAMPLE

First few rows of the triangle are:

1;

2, 1;

4, 2, 1;

4, 4, 2, 1;

6, 4, 4, 2, 1;

6, 6, 4, 4, 2, 1;

8, 6, 6, 4, 4, 2, 1;

...

CROSSREFS

Cf. A135151, A047838, A004736, A128174.

Sequence in context: A118235 A083653 A278290 * A147542 A211956 A128177

Adjacent sequences:  A135149 A135150 A135151 * A135153 A135154 A135155

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Nov 21 2007

STATUS

approved

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Last modified December 8 16:27 EST 2016. Contains 278946 sequences.