|
|
|
|
#13 by N. J. A. Sloane at Sat Sep 12 11:00:25 EDT 2015
|
| LINKS
|
V. Kotesovec, <a href="httphttps://web.telecomoeis.czorg/vaclav.kotesovecwiki/math.htmUser:Vaclav_Kotesovec">Number of ways of placing non-attacking queens, kings, bishops and knights</a> (in English and Czech)
|
|
|
Discussion
|
Sat Sep 12
| 11:00
| OEIS Server: https://oeis.org/edit/global/2459
|
|
|
|
#12 by Vaclav Kotesovec at Tue Mar 04 06:29:59 EST 2014
|
|
|
|
#11 by Vaclav Kotesovec at Tue Mar 04 06:29:42 EST 2014
|
| FORMULA
|
a(n)=2^n*n!*Sum[Binomial[n,i]^3,{i,0,n}]}].
Asymptotic: a(n) ~ 2^(4n+1)*(n-1)!/piPi/sqrt(3) ~ 2^(4n+1)*n^n/e^exp(n*)*sqrt(2/(3*piPi*n)))).
Recurrence: a(n) = ((14*n^2-14*n+4)*a(n-1) + 32*(n-1)^3*a(n-2))/n.
|
| STATUS
|
approved
editing
|
|
|
|
#10 by Joerg Arndt at Sun Jun 02 13:18:19 EDT 2013
|
|
|
|
#9 by Vincenzo Librandi at Sun Jun 02 13:00:25 EDT 2013
|
|
|
|
#8 by Vincenzo Librandi at Sun Jun 02 12:42:07 EDT 2013
|
| LINKS
|
V. Kotesovec, <a href="http://web.telecom.cz/vaclav.kotesovec/math.htm">Number of ways of placing non-attacking queens, kings, bishops and knights</a> (in English and Czech)
V. Kotesovec, <a href="http://web.telecom.cz/vaclav.kotesovec/math.htm">Number of ways of placing non-attacking queens, kings, bishops and knights</a> (in English and Czech)
|
|
|
|
#7 by Vincenzo Librandi at Sun Jun 02 12:41:33 EDT 2013
|
| NAME
|
Number of ways to place n nonattacking bishops on an 2n x 2n toroidal board.
|
| LINKS
|
Vincenzo Librandi, <a href="/A189791/b189791.txt">Table of n, a(n) for n = 1..200</a>
|
| CROSSREFS
|
Cf. A189790, A002465, A000172.
|
| STATUS
|
approved
editing
|
|
|
|
#6 by Russ Cox at Fri Mar 30 19:00:54 EDT 2012
|
| AUTHOR
|
_Vaclav Kotesovec (kotesovec(AT)chello.cz), _, Apr 27 2011
|
|
|
Discussion
|
Fri Mar 30
| 19:00
| OEIS Server: https://oeis.org/edit/global/319
|
|
|
|
#5 by T. D. Noe at Fri Apr 29 14:26:15 EDT 2011
|
|
|
|
#4 by Joerg Arndt at Fri Apr 29 05:43:11 EDT 2011
|
|
|
|