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!)
A252434 Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 4 6 or 7 1

%I #4 Dec 17 2014 10:55:51

%S 641,915,1142,1693,2710,4342,6941,12295,20379,34247,61505,105195,

%T 178817,323844,556603,948521,1716416,2957030,5043301,9112051,15722010,

%U 26825787,48379614,83582702,142663489,256824515,444230495,758496796,1363061440

%N Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 4 6 or 7

%C Row 1 of A252433

%H R. H. Hardin, <a href="/A252434/b252434.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 17*a(n-3) -105*a(n-6) +2*a(n-7) +277*a(n-9) -28*a(n-10) -267*a(n-12) +139*a(n-13) -a(n-14) +19*a(n-15) -291*a(n-16) +11*a(n-17) +85*a(n-18) +232*a(n-19) -34*a(n-20) -25*a(n-21) +6*a(n-22) +14*a(n-23) -85*a(n-25) +35*a(n-26) +25*a(n-28) -25*a(n-29) for n>44

%e Some solutions for n=4

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 17 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 April 25 07:53 EDT 2024. Contains 371964 sequences. (Running on oeis4.)