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!)
A252310 Number of (5+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 1 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 1 3 6 or 7 1

%I

%S 2587,2350,3669,5117,9368,15444,22521,43870,72344,109721,229454,

%T 377280,602057,1358574,2223120,3723881,8973230,14621424,25440425,

%U 64229166,104350128,186159401,483655214,784380720,1419895337,3748625454

%N Number of (5+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 1 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 1 3 6 or 7

%C Row 5 of A252305

%H R. H. Hardin, <a href="/A252310/b252310.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 15*a(n-3) -70*a(n-6) +120*a(n-9) -64*a(n-12) for n>21

%e Some solutions for n=4

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

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 16 2014

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 June 25 15:41 EDT 2022. Contains 354851 sequences. (Running on oeis4.)