

A143593


Triangle read by rows, square of an infinite lower triangular matrix with 1's in the first column and the rest 2's.


1



1, 3, 4, 5, 8, 4, 7, 12, 8, 4, 9, 16, 12, 8, 4, 11, 20, 16, 12, 8, 4, 13, 24, 20, 16, 12, 8, 4, 15, 28, 24, 20, 16, 12, 8, 4, 17, 32, 28, 24, 20, 16, 12, 8, 4, 19, 36, 32, 28, 24, 20, 16, 12, 8, 4
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OFFSET

1,2


COMMENTS

Row sums = A056220 starting with offset 1: (1, 7, 17, 31, 49, 71, 97,...).


LINKS

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


FORMULA

Triangle read by rows, square of an infinite lower triangular matrix with 1's in the first column and the rest 2's. Square of (A000012 * (S(k) * 0^(nk)), 1<=k<=n


EXAMPLE

The square of the infinite lower triangular matrix (1; 1,2; 1,2,2;...) =
1;
3, 4;
5, 8, 4;
7, 12, 8, 4;
9, 16, 12, 8, 4;
11, 20, 16, 12, 8, 4;
13, 24, 20, 16, 12, 8, 4;
...


CROSSREFS

Cf. A056220.
Sequence in context: A325410 A269719 A214626 * A028267 A215497 A092997
Adjacent sequences: A143590 A143591 A143592 * A143594 A143595 A143596


KEYWORD

nonn,tabl


AUTHOR

Gary W. Adamson & Roger L. Bagula, Aug 26 2008


STATUS

approved



