|
| |
|
|
A083474
|
|
T(n)^2-n!, where T(n) is the n-th triangular number.
|
|
0
| |
|
|
0, 7, 30, 76, 105, -279, -4256, -39024, -360855, -3625775, -39912444, -478995516, -6227012519, -87178280175, -1307674353600, -20922789869504, -355687428072591, -6402373705698759, -121645100408795900, -2432902008176595900, -51090942171709386639
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..200
|
|
|
EXAMPLE
| a(3)=T(3)^2-3!=6^2-6=36-6=30
|
|
|
MATHEMATICA
| Table[((n(n+1))/2)^2-n!, {n, 30}] (* From Harvey P. Dale, Nov 23 2011 *)
|
|
|
PROG
| (PARI) t(n)=n*(n+1)/2 for(i=1, 50, print1(", "t(i)^2-i!))
|
|
|
CROSSREFS
| Cf. A000142, A000217.
Sequence in context: A116283 A139274 A086640 * A030440 A045889 A038739
Adjacent sequences: A083471 A083472 A083473 * A083475 A083476 A083477
|
|
|
KEYWORD
| sign,changed
|
|
|
AUTHOR
| Jon Perry (perry(AT)globalnet.co.uk), Jun 08 2003
|
|
|
EXTENSIONS
| Corrected by Harvey P. Dale, Nov 23 2011
|
| |
|
|
