login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A155194 Triangle read by rows: t(n,m)=If[m*(n - m) == 0, 1, n!*(1 - 1/Binomial[n, m])]. 0
1, 1, 1, 1, 1, 1, 1, 4, 4, 1, 1, 18, 20, 18, 1, 1, 96, 108, 108, 96, 1, 1, 600, 672, 684, 672, 600, 1, 1, 4320, 4800, 4896, 4896, 4800, 4320, 1, 1, 35280, 38880, 39600, 39744, 39600, 38880, 35280, 1, 1, 322560, 352800, 358560, 360000, 360000, 358560, 352800 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,8

COMMENTS

Row sums are {1, 2, 3, 10, 58, 410, 3230, 28034, 267266, 2787842, 31662722,...}

LINKS

Table of n, a(n) for n=0..52.

EXAMPLE

{1},

{1, 1},

{1, 1, 1},

{1, 4, 4, 1},

{1, 18, 20, 18, 1},

{1, 96, 108, 108, 96, 1},

{1, 600, 672, 684, 672, 600, 1},

{1, 4320, 4800, 4896, 4896, 4800, 4320, 1},

{1, 35280, 38880, 39600, 39744, 39600, 38880, 35280, 1},

{1, 322560, 352800, 358560, 360000, 360000, 358560, 352800, 322560, 1},

{1, 3265920, 3548160, 3598560, 3611520, 3614400, 3611520, 3598560, 3548160, 3265920, 1}

MATHEMATICA

Table[Table[ If[m*(n - m) == 0, 1, n!*(1 - 1/Binomial[n, m])], {m, 0, n}], {n, 0, 10}];

Flatten[%]

CROSSREFS

Sequence in context: A075613 A221837 A189150 * A080044 A128433 A089746

Adjacent sequences:  A155191 A155192 A155193 * A155195 A155196 A155197

KEYWORD

nonn,tabl

AUTHOR

Roger L. Bagula, Jan 21 2009

EXTENSIONS

Edited by N. J. A. Sloane, Jan 25 2009

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 19 06:47 EDT 2019. Contains 324218 sequences. (Running on oeis4.)