%I #4 Jul 03 2016 20:21:24

%S 32,1296,16524,301784,5634776,105328812,1980677448,37188898120,

%T 699226867860,13139454740876,246989200003420,4642070954166124,

%U 87252983103535936,1639953977382243676,30824192792654598004

%N Number of 7Xn 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) or (-1,0) and new values introduced in order 0..2.

%C Row 7 of A274728.

%H R. H. Hardin, <a href="/A274732/b274732.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 21*a(n-1) +46*a(n-2) -2078*a(n-3) +7099*a(n-4) +30390*a(n-5) -199330*a(n-6) +32493*a(n-7) +1799239*a(n-8) -2883655*a(n-9) -6458651*a(n-10) +19972172*a(n-11) +4488011*a(n-12) -63185111*a(n-13) +38593516*a(n-14) +97573203*a(n-15) -147528893*a(n-16) +26937123*a(n-17) +105357461*a(n-18) -172813699*a(n-19) +142443589*a(n-20) +18232365*a(n-21) -135277945*a(n-22) +91577781*a(n-23) -13939351*a(n-24) -6667960*a(n-25) +1422372*a(n-26) +709307*a(n-27) -229702*a(n-28) +8892*a(n-29) +1296*a(n-30) for n>34

%e Some solutions for n=3

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

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

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

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

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

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

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

%Y Cf. A274728.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 03 2016