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!)
A206272 Number of (n+1) X 4 0..2 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors. 1

%I #7 Dec 11 2015 21:25:07

%S 1233,3168,12429,39306,133866,437340,1528920,4972464,17378730,

%T 56812524,197823117,647998686,2252305758,7394389266,25660071480,

%U 84368598492,292322882925,962789033730,3330544867176,10985542604052,37947971462754

%N Number of (n+1) X 4 0..2 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors.

%C Column 3 of A206277.

%H R. H. Hardin, <a href="/A206272/b206272.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 12*a(n-2) +22*a(n-4) +2*a(n-5) -340*a(n-6) +44*a(n-7) -30*a(n-8) +302*a(n-9) -3011*a(n-10) +198*a(n-11) +10251*a(n-12) -5274*a(n-13) +71024*a(n-14) -31264*a(n-15) -65095*a(n-16) +356*a(n-17) -100260*a(n-18) -55796*a(n-19) +285507*a(n-20) -129166*a(n-21) -253871*a(n-22) +145844*a(n-23) -497761*a(n-24) -139938*a(n-25) +558865*a(n-26) -259172*a(n-27) +120937*a(n-28) -90988*a(n-29) -849840*a(n-30) -208948*a(n-31) -309854*a(n-32) +4632*a(n-33) +119043*a(n-34) +74848*a(n-35) +43437*a(n-36) +90324*a(n-37) +60444*a(n-38) +22592*a(n-39) +12708*a(n-40) +4144*a(n-41) +8976*a(n-42) +1024*a(n-43) +1024*a(n-44) for n>49.

%e Some solutions for n=4:

%e ..0..0..1..2....1..0..1..0....2..1..1..0....0..2..2..1....2..2..0..2

%e ..1..1..2..2....2..0..0..2....2..0..0..2....2..2..2..1....2..1..2..2

%e ..1..1..2..2....2..0..0..0....2..0..0..2....2..2..0..2....1..2..2..2

%e ..2..2..0..0....1..2..0..0....0..1..1..0....0..0..1..1....2..2..2..0

%e ..2..2..2..1....1..1..2..2....0..1..1..0....0..0..1..1....2..2..0..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 05 2012

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 July 20 08:10 EDT 2024. Contains 374442 sequences. (Running on oeis4.)