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!)
A251876 T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7 9

%I #4 Dec 10 2014 09:20:17

%S 1038,2146,2146,3092,5632,3092,5756,7160,7160,5756,11008,15116,7080,

%T 15116,11008,18400,36852,9936,9936,36852,18400,32372,41816,18464,

%U 13152,18464,41816,32372,60292,99808,31296,31520,31520,31296,99808,60292

%N T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7

%C Table starts

%C ...1038...2146...3092...5756...11008...18400....32372....60292....100612

%C ...2146...5632...7160..15116...36852...41816....99808...169196....246152

%C ...3092...7160...7080...9936...18464...31296....40816....93176....140408

%C ...5756..15116...9936..13152...31520...46464....62720...164480....252736

%C ..11008..36852..18464..31520..107040..151704...267872...924272...1402224

%C ..18400..41816..31296..46464..151704..309144...506656..1847872...4274816

%C ..32372..99808..40816..62720..267872..506656...893120..3499888...8000000

%C ..60292.169196..93176.164480..924272.1847872..3499888.19032128..47257792

%C .100612.246152.140408.252736.1402224.4274816..8000000.47257792.165273152

%C .176372.568040.223728.389376.2561696.7487600.15317248.93188992.341663728

%H R. H. Hardin, <a href="/A251876/b251876.txt">Table of n, a(n) for n = 1..337</a>

%F Empirical for column k:

%F k=1: [linear recurrence of order 18] for n>23

%F k=2: [order 27] for n>33

%F k=3: a(n) = 15*a(n-3) -50*a(n-6) -160*a(n-9) +1056*a(n-12) -1280*a(n-15) for n>22

%F k=4: a(n) = 8*a(n-3) +16*a(n-6) -128*a(n-9) for n>17

%F k=5: a(n) = 21*a(n-3) -88*a(n-6) -336*a(n-9) +1664*a(n-12) for n>21

%F k=6: [order 18] for n>28

%F k=7: a(n) = 29*a(n-3) -168*a(n-6) for n>17

%e Some solutions for n=4 k=4

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

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

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

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

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

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

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_, Dec 10 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 23 07:16 EDT 2024. Contains 371905 sequences. (Running on oeis4.)