The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
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!)
A184063 Number of (n+1) X 2 binary arrays with rows and columns in nondecreasing order and with no 2 X 2 subblock sum differing from a horizontal or vertical neighbor subblock sum by more than one. 1

%I #8 Apr 11 2018 08:10:24

%S 7,11,20,34,54,81,116,160,214,279,356,446,550,669,804,956,1126,1315,

%T 1524,1754,2006,2281,2580,2904,3254,3631,4036,4470,4934,5429,5956,

%U 6516,7110,7739,8404,9106,9846,10625,11444,12304,13206,14151,15140,16174,17254

%N Number of (n+1) X 2 binary arrays with rows and columns in nondecreasing order and with no 2 X 2 subblock sum differing from a horizontal or vertical neighbor subblock sum by more than one.

%C Column 1 of A184071.

%H R. H. Hardin, <a href="/A184063/b184063.txt">Table of n, a(n) for n = 1..200</a>

%F Conjectures from _Colin Barker_, Apr 11 2018: (Start)

%F G.f.: x*(7 - 17*x + 18*x^2 - 8*x^3 + x^4) / (1 - x)^4.

%F a(n) = (n^3 + 6*n^2 + 5*n + 24) / 6 for n>1.

%F a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>5.

%F (End)

%e Some solutions for 3 X 2:

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

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

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

%e ...

%e ...1.......2.......0.......3.......0.......2.......1.......2.......2.......2...

%e ...2.......2.......1.......4.......0.......3.......2.......3.......2.......2...

%Y Cf. A184071.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 09 2011

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 May 15 02:15 EDT 2024. Contains 372536 sequences. (Running on oeis4.)