



1, 1, 1, 2, 1, 2, 2, 2, 1, 3, 3, 2, 3, 1, 4, 3, 3, 2, 4, 1, 5, 4, 3, 4, 2, 5, 1, 6, 4, 4, 3, 5, 2, 6, 1, 7, 5, 4, 5, 3, 6, 2, 7, 1, 8, 5, 5, 4, 6, 3, 7, 2, 8, 1, 9, 6, 5, 6, 4, 7, 3, 8, 2, 9, 1, 10, 6, 6, 5, 7, 4, 8, 3, 9, 2, 10, 1, 11
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OFFSET

1,4


COMMENTS

Row sums = A000982 starting with offset 1: (1, 2, 5, 8, 13, 18, 25,...).


LINKS

Table of n, a(n) for n=1..78.


FORMULA

Triangle read by rows, A000012(signed) * A145677 * A000012. A000012(signed) = an infinite lower triangular matrix with (1,1,1,1,...) in every column. A145677 = an infinite lower triangular matrix with all 1's as the left border, right border = (1, 1, 2, 3, 4, 5,...), and the rest zeros.


EXAMPLE

First few rows of the triangle =
1;
1, 1;
2, 1, 2;
2, 2, 1, 3;
3, 2, 3, 1, 4;
3, 3, 2, 4, 1, 5;
4, 3, 4, 2, 5, 1, 6;
4, 4, 3, 5, 2, 6, 1, 7;
5, 4, 5, 3, 6, 2, 7, 1, 8;
5, 5, 4, 6, 3, 7, 2, 8, 1, 9;
6, 5, 6, 4, 7, 3, 8, 2, 9, 1, 10;
6, 6, 5, 7, 4, 8, 3, 9, 2, 10, 1, 11;
7, 6, 7, 5, 8, 4, 9, 3, 10, 2, 11, 1, 12;
7, 7, 6, 8, 5, 9, 4, 10, 3, 11, 2, 12, 1, 13;
...


CROSSREFS

Cf. A145677, A000982
Sequence in context: A105149 A295894 A068307 * A303428 A223853 A023645
Adjacent sequences: A158943 A158944 A158945 * A158947 A158948 A158949


KEYWORD

nonn,tabl


AUTHOR

Gary W. Adamson, Mar 31 2009


STATUS

approved



