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!)
A280175 Number of nX3 0..1 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. 1

%I #4 Dec 28 2016 06:59:34

%S 0,12,60,279,1082,3931,13720,46467,153650,499289,1598693,5059881,

%T 15855622,49273183,152010000,466006394,1420614227,4309242893,

%U 13013193556,39139655092,117289714264,350310455965,1043078536630,3097120192877

%N Number of nX3 0..1 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

%C Column 3 of A280180.

%H R. H. Hardin, <a href="/A280175/b280175.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 9*a(n-1) -24*a(n-2) -9*a(n-3) +147*a(n-4) -213*a(n-5) -80*a(n-6) +567*a(n-7) -624*a(n-8) -30*a(n-9) +711*a(n-10) -687*a(n-11) +215*a(n-12) +84*a(n-13) +3*a(n-14) -86*a(n-15) +27*a(n-16) +6*a(n-17) -17*a(n-18) -18*a(n-19) -6*a(n-20) -a(n-21) for n>28

%e Some solutions for n=4

%e ..0..0..0. .0..1..1. .0..1..1. .0..0..0. .0..1..1. .0..1..1. .0..1..0

%e ..0..1..0. .1..1..0. .0..1..1. .1..1..0. .1..1..1. .0..1..0. .0..0..0

%e ..1..0..0. .1..1..1. .0..1..0. .1..1..1. .1..0..1. .1..0..0. .0..0..0

%e ..1..1..1. .1..1..1. .1..1..0. .0..1..1. .1..1..1. .0..0..0. .1..0..0

%Y Cf. A280180.

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 28 2016

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 April 25 03:15 EDT 2024. Contains 371964 sequences. (Running on oeis4.)