|
|
A269950
|
|
Triangle read by rows, T(n,k) = denominator(binomial(1/2,n-k))*binomial(n+1/2, k+1/2), for n>=0 and 0<=k<=n.
|
|
2
|
|
|
1, 3, 1, 15, 5, 1, 35, 35, 7, 1, 315, 105, 63, 9, 1, 693, 1155, 231, 99, 11, 1, 3003, 3003, 3003, 429, 143, 13, 1, 6435, 15015, 9009, 6435, 715, 195, 15, 1, 109395, 36465, 51051, 21879, 12155, 1105, 255, 17, 1, 230945, 692835, 138567, 138567, 46189, 20995, 1615, 323, 19, 1
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
EXAMPLE
|
Triangle starts:
[1]
[3, 1]
[15, 5, 1]
[35, 35, 7, 1]
[315, 105, 63, 9, 1]
[693, 1155, 231, 99, 11, 1]
[3003, 3003, 3003, 429, 143, 13, 1]
[6435, 15015, 9009, 6435, 715, 195, 15, 1]
|
|
PROG
|
(Sage)
A269950 = lambda n, k: binomial(1/2, n-k).denom()*binomial(n+1/2, k+1/2)
for n in range(8): print([A269950(n, k) for k in (0..n)])
|
|
CROSSREFS
|
|
|
KEYWORD
|
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|