login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A080291 a(n)=(-1)^(n+1)n^n(n+(1/12)(n^2-1)). 0
1, -9, 99, -1344, 21875, -416016, 9058973, -222298112, 6069587661, -182500000000, 5991545082831, -213243402387456, 8177627877990831, -336138206473129984, 14742427642822265625, -687141216745680797696, 33916850737339807331257 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(n) is the determinant of the n X n matrix M with M(i,i)=2i-n, M(i.j)=i+j.
LINKS
FORMULA
a(n)=(-1)^(n+1)n^n(n+(1/12)(n^2-1)). a(n)=(-1)^n(n^n-n^(n-1)A002378(n)-n^(n-2)A002415(n)).
MATHEMATICA
Table[(-1)^(n + 1)n^n(n + (n^2 - 1)/12), {n, 1, 17}]
CROSSREFS
Sequence in context: A015685 A051581 A356100 * A215243 A113395 A070068
KEYWORD
easy,sign
AUTHOR
Mario Catalani (mario.catalani(AT)unito.it), Feb 13 2003
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 14 03:22 EDT 2024. Contains 371652 sequences. (Running on oeis4.)