

A140169


Triangle read by rows, iterates of X * [1,0,0,0,...] where X = an infinite bidiagonal matrix with (2,1,2,1,2,1,...) in the main diagonal, (1,2,1,2,1,2,...) in the subdiagonal and the rest zeros.


0



1, 2, 1, 4, 3, 2, 8, 7, 10, 2, 16, 15, 34, 12, 4, 32, 31, 98, 46, 32, 4, 64, 63, 258, 144, 156, 36, 8, 128, 127, 642, 402, 600, 192, 88, 8, 256, 255, 1358, 1044, 2004, 792, 560, 96, 16, 512, 511, 3586, 2582, 6096, 2796, 2704, 656, 224, 16, 1024, 1023, 8194, 6168, 17356
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OFFSET

0,2


COMMENTS

Row sums = 3^n: (1, 3, 9, 27, 81,...)


LINKS

Table of n, a(n) for n=0..59.


FORMULA

Triangle read by rows, iterates of X * [1,0,0,0,...]; where X = an infinite bidiagonal matrix with [2, 1, 2, 1, 2,...] in the main diagonal, [1, 1, 1,...] in the subdiagonal and rest zeros.


EXAMPLE

First few rows of the triangle are:
1;
2, 1;
4, 3, 2;
8, 7, 10, 2;
16, 15, 34, 12, 4;
32, 31, 98, 46, 32, 4;
64, 63, 258, 144, 156, 36, 8;
128, 126, 642, 402, 600, 192, 88, 8;
...


CROSSREFS

Sequence in context: A182013 A144333 A126136 * A124731 A210658 A143122
Adjacent sequences: A140166 A140167 A140168 * A140170 A140171 A140172


KEYWORD

nonn,tabl


AUTHOR

Gary W. Adamson, May 10 2008


STATUS

approved



