|
Search: id:A124376
|
|
|
| A124376 |
|
Number triangle with column k generated by x^k*(1+2kx+C(k,2)*x^2)/(1-x)^(k+1). |
|
+0
1
|
|
| 1, 1, 1, 1, 4, 1, 1, 7, 7, 1, 1, 10, 19, 10, 1, 1, 13, 37, 37, 13, 1, 1, 16, 61, 92, 61, 16, 1, 1, 19, 91, 185, 185, 91, 19, 1, 1, 22, 127, 326, 440, 326, 127, 22, 1, 1, 25, 169, 525, 896, 896, 525, 169, 25, 1, 1, 28, 217, 792
(list; table; graph; listen)
|
|
|
OFFSET
|
0,5
|
|
|
COMMENT
|
Columns include A016777,A003215,A096000. T(n,k)=T(n-k,k).
|
|
FORMULA
|
Number triangle T(n,k)=sum{j=0..n, C(k,k-j)*C(n-j,k)*C(2,j)}*[k<=n]
|
|
EXAMPLE
|
Triangle begins
1,
1, 1,
1, 4, 1,
1, 7, 7, 1,
1, 10, 19, 10, 1,
1, 13, 37, 37, 13, 1,
1, 16, 61, 92, 61, 16, 1,
1, 19, 91, 185, 185, 91, 19, 1
|
|
CROSSREFS
|
Adjacent sequences: A124373 A124374 A124375 this_sequence A124377 A124378 A124379
Sequence in context: A046550 A016521 A131060 this_sequence A047671 A081577 A073697
|
|
KEYWORD
|
easy,nonn,tabl
|
|
AUTHOR
|
Paul Barry (pbarry(AT)wit.ie), Oct 28 2006
|
|
|
Search completed in 0.002 seconds
|
