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!)
A175411 a(n) = Sum_{i=(n*n-n+2)/2..(n*n+n)/2} i!. 0
1, 8, 864, 4037040, 1401598598400, 53652268264218624000, 316196664157721349185863680000, 382630662500715988102392981826830336000000, 122342346998826334909002798912467017444232685158400000000, 12931604174610554670466196146308122246477496321113350463375278080000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

a(4) = 7! + 8! + 9! + 10! = 4037074.

PROG

(PARI) a(n)= sum(i=(n^2-n+2)/2, (n^2+n)/2, i!); \\ Michel Marcus, Mar 15 2022

CROSSREFS

Cf. A000142.

Sequence in context: A159707 A097818 A262379 * A027725 A265239 A290023

Adjacent sequences:  A175408 A175409 A175410 * A175412 A175413 A175414

KEYWORD

easy,nonn

AUTHOR

Ctibor O. Zizka, May 07 2010

EXTENSIONS

a(4) corrected and more terms from Michel Marcus, Mar 15 2022

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 July 4 16:52 EDT 2022. Contains 355081 sequences. (Running on oeis4.)