

A106522


A Pascal type matrix based on the tribonacci numbers.


3



1, 1, 1, 2, 2, 1, 4, 4, 3, 1, 7, 8, 7, 4, 1, 13, 15, 15, 11, 5, 1, 24, 28, 30, 26, 16, 6, 1, 44, 52, 58, 56, 42, 22, 7, 1, 81, 96, 110, 114, 98, 64, 29, 8, 1, 149, 177, 206, 224, 212, 162, 93, 37, 9, 1, 274, 326, 383, 430, 436, 374, 255, 130, 46, 10, 1, 504, 600, 709, 813, 866, 810
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OFFSET

0,4


COMMENTS

Row sums are A001590(n+3), diagonal sums are A106523. Row sums of A106522 mod 2 are A106524.


LINKS

Table of n, a(n) for n=0..71.


FORMULA

Riordan array (1/(1xx^2x^3), x/(1x)); Number triangle T(n, 0)=A000073(n+2), T(n, k)=T(n1, k1)+T(n1, k).


EXAMPLE

Triangle begins
1;
1,1;
2,2,1;
4,4,3,1;
7,8,7,4,1;
13,13,15,11,5,1;


CROSSREFS

Sequence in context: A107356 A329854 A124725 * A128175 A104040 A332601
Adjacent sequences: A106519 A106520 A106521 * A106523 A106524 A106525


KEYWORD

easy,nonn,tabl


AUTHOR

Paul Barry, May 06 2005


STATUS

approved



