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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A218843 Unmatched value maps: number of 2 X n binary arrays indicating the locations of corresponding elements not equal to any horizontal or antidiagonal neighbor in a random 0..1 2 X n array. 1

%I

%S 1,7,20,57,156,438,1220,3398,9468,26380,73496,204780,570556,1589672,

%T 4429140,12340436,34382820,95797176,266909376,743660900,2071982512,

%U 5772942284,16084528900,44814595084,124862092120,347889834096

%N Unmatched value maps: number of 2 X n binary arrays indicating the locations of corresponding elements not equal to any horizontal or antidiagonal neighbor in a random 0..1 2 X n array.

%C Row 2 of A218842.

%H R. H. Hardin, <a href="/A218843/b218843.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) + a(n-2) + 3*a(n-3) + 2*a(n-5) + 2*a(n-6) - 2*a(n-7) for n>9.

%F Empirical g.f.: x*(1 + 5*x + 5*x^2 + 7*x^3 + x^4 + 7*x^5 + x^6 - 2*x^8) / (1 - 2*x - x^2 - 3*x^3 - 2*x^5 - 2*x^6 + 2*x^7). - _Colin Barker_, Jul 24 2018

%e Some solutions for n=3:

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

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

%Y Cf. A218842.

%K nonn

%O 1,2

%A _R. H. Hardin_, Nov 07 2012

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.

Last modified April 7 04:20 EDT 2020. Contains 333292 sequences. (Running on oeis4.)