login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A221405 Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor, with every occupancy equal to zero or two 1

%I

%S 4,44,436,4518,47156,492102,5133044,53529806,558164472,5819704716,

%T 60677191216,632619159318,6595610902832,68764677891112,

%U 716926331557236,7474513869766556,77927543824707370,812454058048811426

%N Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor, with every occupancy equal to zero or two

%C Column 4 of A221408

%H R. H. Hardin, <a href="/A221405/b221405.txt">Table of n, a(n) for n = 1..94</a>

%F Empirical: a(n) = 19*a(n-1) -110*a(n-2) +250*a(n-3) -446*a(n-4) +939*a(n-5) -1112*a(n-6) -343*a(n-7) -822*a(n-8) +692*a(n-9) +1957*a(n-10) +2810*a(n-11) -1975*a(n-12) -59*a(n-13) -2679*a(n-14) +738*a(n-15) +1088*a(n-16) +1258*a(n-17) -418*a(n-18) -562*a(n-19) +192*a(n-20) +336*a(n-21) +32*a(n-22) -32*a(n-23)

%e Some solutions for n=3

%e ..0..2..2..0....0..2..0..2....2..2..0..2....2..2..0..2....0..2..0..0

%e ..2..2..0..0....0..2..0..2....0..0..0..2....0..2..0..0....2..0..0..2

%e ..0..0..2..2....2..0..0..2....2..2..0..0....2..0..2..0....2..2..2..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 15 2013

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 20 10:00 EDT 2021. Contains 345162 sequences. (Running on oeis4.)