|
| |
|
|
A127893
|
|
Riordan array (1/(1-x)^3,x/(1-x)^3).
|
|
4
| |
|
|
1, 3, 1, 6, 6, 1, 10, 21, 9, 1, 15, 56, 45, 12, 1, 21, 126, 165, 78, 15, 1, 28, 252, 495, 364, 120, 18, 1, 36, 462, 1287, 1365, 680, 171, 21, 1, 45, 792, 3003, 4368, 3060, 1140, 231, 24, 1, 55, 1287, 6435, 12376
(list; table; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
COMMENTS
| Row sums are A052529(n+1). Diagonal sums are A095263. Inverse is A127894.
|
|
|
FORMULA
| Number triangle T(n,k)=C(n+2k+2,n-k)
|
|
|
EXAMPLE
| Triangle begins
1,
3, 1,
6, 6, 1,
10, 21, 9, 1,
15, 56, 45, 12, 1,
21, 126, 165, 78, 15, 1,
28, 252, 495, 364, 120, 18, 1,
36, 462, 1287, 1365, 680, 171, 21, 1,
45, 792, 3003, 4368, 3060, 1140, 231, 24, 1,
55, 1287, 6435, 12376, 11628, 5985, 1771, 300, 27, 1,
66, 2002, 12870, 31824, 38760, 26334, 10626, 2600, 378, 30, 1
|
|
|
CROSSREFS
| Sequence in context: A153091 A179069 A124847 * A127895 A152685 A116412
Adjacent sequences: A127890 A127891 A127892 * A127894 A127895 A127896
|
|
|
KEYWORD
| easy,nonn,tabl
|
|
|
AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Feb 04 2007
|
| |
|
|
