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!)
A268771 Number of nX5 0..2 arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1

%I

%S 96,248,1524,10340,64112,387146,2258084,12951796,73011192,406925194,

%T 2244513800,12281806624,66734787464,360505595710,1937557458852,

%U 10367717536488,55261185262316,293537189567482,1554428843176696

%N Number of nX5 0..2 arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once.

%C Column 5 of A268774.

%H R. H. Hardin, <a href="/A268771/b268771.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) +28*a(n-2) -62*a(n-3) -314*a(n-4) +78*a(n-5) +867*a(n-6) +6*a(n-7) -859*a(n-8) +46*a(n-9) +215*a(n-10) -8*a(n-11) -16*a(n-12) for n>14

%e Some solutions for n=4

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

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

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

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

%Y Cf. A268774.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 13 2016

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 January 26 01:48 EST 2020. Contains 331270 sequences. (Running on oeis4.)