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A083474
T(n)^2-n!, where T(n) is the n-th triangular number.
1
0, 7, 30, 76, 105, -279, -4256, -39024, -360855, -3625775, -39912444, -478995516, -6227012519, -87178280175, -1307674353600, -20922789869504, -355687428072591, -6402373705698759, -121645100408795900, -2432902008176595900, -51090942171709386639
OFFSET
1,2
LINKS
EXAMPLE
a(3)=T(3)^2-3!=6^2-6=36-6=30
MATHEMATICA
Table[((n(n+1))/2)^2-n!, {n, 30}] (* Harvey P. Dale, Nov 23 2011 *)
PROG
(PARI) t(n)=n*(n+1)/2 for(i=1, 50, print1(", "t(i)^2-i!))
CROSSREFS
Sequence in context: A116283 A139274 A086640 * A030440 A256225 A339196
KEYWORD
sign
AUTHOR
Jon Perry, Jun 08 2003
EXTENSIONS
Corrected by Harvey P. Dale, Nov 23 2011
STATUS
approved