|
| |
|
|
A114195
|
|
Riordan array (1/(1-3x),x(1-x)/(1-3x)^2).
|
|
2
| |
|
|
1, 3, 1, 9, 8, 1, 27, 45, 13, 1, 81, 216, 106, 18, 1, 243, 945, 690, 192, 23, 1, 729, 3888, 3915, 1574, 303, 28, 1, 2187, 15309, 20223, 10941, 2993, 439, 33, 1, 6561, 58320, 97524, 67788, 24598, 5072, 600, 38, 1, 19683, 216513, 446148, 385560, 177498
(list; table; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
COMMENTS
| Row sums are A082685. Diagonal sums are A114196.
|
|
|
FORMULA
| T(n, k)=sum{j=0..n, C(n, j)C(j+k, 2k)2^(j-k)}; T(n, k)=sum{j=0..n-k, C(k, j)C(n+k-j, 2k)(-1)^j*3^(n-k-j)}.
|
|
|
EXAMPLE
| Triangle begins
1;
3, 1;
9, 8, 1;
27, 45, 13, 1;
81, 216, 106, 18, 1;
243, 945, 690, 192, 23, 1;
|
|
|
CROSSREFS
| Sequence in context: A136320 A201840 A088640 * A185948 A016601 A193031
Adjacent sequences: A114192 A114193 A114194 * A114196 A114197 A114198
|
|
|
KEYWORD
| easy,nonn,tabl
|
|
|
AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Nov 16 2005
|
| |
|
|
