|
Search: id:A057003
|
|
|
| A057003 |
|
Write the natural numbers in groups: 1; 2,3; 4,5,6; 7,8,9,10; ... and multiple the members of each group. |
|
+0
5
|
|
| 1, 6, 120, 5040, 360360, 39070080, 5967561600, 1220096908800, 321570878428800, 106137499051584000, 42873948150095462400, 20803502274492921984000, 11938961126118491232768000, 7998487694738166709923840000
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
COMMENT
|
Each group begins with a triangular number + 1 and proceeds until the next triangular number.
|
|
FORMULA
|
(n (n + 1)/2)!/((n - 1) n /2)!
|
|
MATHEMATICA
|
Table[(n (n + 1)/2)!/((n - 1) n /2)!, {n, 1, 15}]
|
|
CROSSREFS
|
Cf. A006003.
Sequence in context: A029697 A126448 A126446 this_sequence A096718 A096720 A009445
Adjacent sequences: A057000 A057001 A057002 this_sequence A057004 A057005 A057006
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 09 2000
|
|
|
Search completed in 0.002 seconds
|
