|
|
A139173
|
|
a(n) = n!/3 - 1.
|
|
9
|
|
|
1, 7, 39, 239, 1679, 13439, 120959, 1209599, 13305599, 159667199, 2075673599, 29059430399, 435891455999, 6974263295999, 118562476031999, 2134124568575999, 40548366802943999, 810967336058879999
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
3,2
|
|
COMMENTS
|
Original definition: Natural numbers of the form (n! - 3)/3.
|
|
LINKS
|
|
|
FORMULA
|
E.g.f.: (6 - 3*x^2 - x^3)/(6*(1-x)) - exp(x). - G. C. Greubel, Oct 18 2018
|
|
MATHEMATICA
|
Table[(n! - 3)/3, {n, 3, 20}]
|
|
PROG
|
(PARI) for(n=3, 25, print1((n!-3)/3, ", ")) \\ G. C. Greubel, Oct 18 2018
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|