|
Search: id:A035020
|
|
|
| A035020 |
|
One sixth of 9-factorial numbers. |
|
+0
13
|
|
| 1, 15, 360, 11880, 498960, 25446960, 1526817600, 105350414400, 8217332323200, 714907912118400, 68631159563366400, 7206271754153472000, 821514979973495808000, 101046342536739984384000
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
LINKS
|
Index entries for sequences related to factorial numbers
|
|
FORMULA
|
6*a(n) = (9*n-3)(!^9) := product(9*j-3, j=1..n) = 3^n*2*A034000(n), 2*A034000(n)=(3*n-1)(!^3) := product(3*j-1, j=1..n); E.g.f. (-1+(1-9*x)^(-2/3))/6.
|
|
MATHEMATICA
|
s=1; lst={s}; Do[s+=n*s; AppendTo[lst, s], {n, 14, 2*5!, 9}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 08 2008]
|
|
CROSSREFS
|
Cf. A007559, A034171, A045756, A035012, A035013, A035017, A035018, A035020-A035023.
Sequence in context: A012787 A030049 A012486 this_sequence A087330 A035274 A145409
Adjacent sequences: A035017 A035018 A035019 this_sequence A035021 A035022 A035023
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de)
|
|
|
Search completed in 0.002 seconds
|
