|
%I #14 Nov 18 2023 22:24:09
%S 1,5,19,217,4076,164258,12285477,1834600977,527717587843,
%T 296979228487760,324881629286870822,692625866382651263578,
%U 2874716493700380888930840,23237986479606982160703729647,365788614113216462103977935612524,11213018647250714014261414954480048385
%N Number of binary arrangements without adjacent 1's on n X n hexagonal staggered torus shifted for odd n.
%D Steven R. Finch, Mathematical Constants, Cambridge, 2003, pp. 342-349.
%H Steven R. Finch, <a href="http://www.people.fas.harvard.edu/~sfinch/constant/square/square.html">Hard Square Entropy Constant</a> [Broken link]
%H Steven R. Finch, <a href="http://web.archive.org/web/20010605012506/http://www.mathsoft.com/asolve/constant/square/square.html">Hard Square Entropy Constant</a> [From the Wayback machine]
%e Neighbors for n=4:
%e :\|/ | \|/ |
%e :-o--o--o--o-
%e : | /|\ | /|\
%e :\|/ | \|/ |
%e :-o--o--o--o-
%e : | /|\ | /|\
%e :\|/ | \|/ |
%e :-o--o--o--o-
%e : | /|\ | /|\
%e :\|/ | \|/ |
%e :-o--o--o--o-
%e : | /|\ | /|\
%e Neighbors for n=5:
%e :\|/ | \|/ | \|
%e :-o--o--o--o--o-
%e : | /|\ | /|\ |\
%e :\|/ | \|/ | \|
%e :-o--o--o--o--o-
%e : | /|\ | /|\ |\
%e :\|/ | \|/ | \|
%e :-o--o--o--o--o-
%e : | /|\ | /|\ |\
%e :\|/ | \|/ | \|
%e :-o--o--o--o--o-
%e : | /|\ | /|\ |\
%e :\|/ | \|/ | \|
%e :-o--o--o--o--o-
%e : | /|\ | /|\ |\
%Y For bent instead of shifted for odd n see A066865.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 02 2002
%E More terms from _Sean A. Irvine_, Nov 18 2023
| 