[go: up one dir, main page]

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!)
Revision History for A054592 (Underlined text is an addition; strikethrough text is a deletion.)

Showing entries 1-10 | older changes
A054592 Number of disconnected labeled graphs with n nodes.
(history; published version)
#20 by Michael De Vlieger at Fri Feb 24 16:27:57 EST 2023
STATUS

proposed

approved

#19 by Peter Luschny at Fri Feb 24 15:58:03 EST 2023
STATUS

editing

proposed

#18 by Peter Luschny at Fri Feb 24 15:57:26 EST 2023
FORMULA

a(n) = n) = [!*[x^n] (](g - log(g) - 1) where g = Sum_{n>=0} 2^binomial(n, 2) * x^n / n!. - Geoffrey Critzer, Nov 11 2011

EXTENSIONS

ExtendedEdited and extended with a(0) = 0 by Peter Luschny, Feb 24 2023

#17 by Peter Luschny at Fri Feb 24 15:51:10 EST 2023
FORMULA

a(n) = [x^n] (g - log(g) - 1) where g = Sum_{n>=0} 2^binomial(n, 2) * x^n / n!. - Geoffrey Critzer, Nov 11 2011

Discussion
Fri Feb 24 15:55
Peter Luschny: Critzer's transform series formula extracted to the formula section.
#16 by Peter Luschny at Fri Feb 24 15:47:13 EST 2023
DATA

0, 0, 1, 4, 26, 296, 6064, 230896, 16886864, 2423185664, 687883494016, 387139470010624, 432380088071584256, 959252253993204724736, 4231267540316814507357184, 37138269572860613284747227136, 649037449132671895468073434916864, 22596879313063804832510513481261154304

MAPLE

upto := 18: g := add(2^binomial(n, 2) * x^n / n!, n = 0..upto+1):

ser := series(g - log(g) - 1, x, upto+1):

seq(n!*coeff(ser, x, n), n = 0..upto); # Peter Luschny, Feb 24 2023

#15 by Peter Luschny at Fri Feb 24 15:36:21 EST 2023
OFFSET

10,4

#14 by Peter Luschny at Fri Feb 24 15:35:56 EST 2023
FORMULA

a(n) = Sum_{k=0..n-1} A360604(n, k) * A001187(k). - Peter Luschny, Feb 24 2023

CROSSREFS

Cf. A001187, A000719, A360604.

#13 by Peter Luschny at Fri Feb 24 15:31:30 EST 2023
DATA

0, 0, 1, 4, 26, 296, 6064, 230896, 16886864, 2423185664, 687883494016, 387139470010624, 432380088071584256, 959252253993204724736, 4231267540316814507357184, 37138269572860613284747227136

OFFSET

1,34

EXTENSIONS

Extended with a(0) = 0 by Peter Luschny, Feb 24 2023

#12 by Peter Luschny at Fri Feb 24 15:29:30 EST 2023
COMMENTS

a(n)=2^binomial(n,2)-A001187(n)

FORMULA

a(n) = 2^binomial(n, 2) - A001187(n).

STATUS

approved

editing

#11 by Charles R Greathouse IV at Sun Aug 03 14:29:46 EDT 2014
MATHEMATICA

g=Sum[2^Binomial[n, 2]x^n/n!, {n, 0, 20}]; Range[0, 20]! CoefficientList[Series[g-Log[g]-1, {x, 0, 20}], x] (* ] (* _Geoffrey Critzer, _, Nov 11 2011 *)

Discussion
Sun Aug 03 14:29
OEIS Server: https://oeis.org/edit/global/2274

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 August 29 15:03 EDT 2024. Contains 375517 sequences. (Running on oeis4.)