A274857 - OEIS

%I #4 Jul 09 2016 11:02:05

%S 32,729,542,2585,12102,58775,289494,1426688,7031552,34766640,

%T 172447382,856198165,4249077675,21078145330,104568950459,518896515145,

%U 2575174869347,12779650282427,63417621140877,314701428995532

%N Number of nX7 0..2 arrays with no element equal to any value at offset (-1,0) (0,-1) or (-2,-2) and new values introduced in order 0..2.

%C Column 7 of A274858.

%H R. H. Hardin, <a href="/A274857/b274857.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 21*a(n-1) -209*a(n-2) +1330*a(n-3) -6059*a(n-4) +20839*a(n-5) -55739*a(n-6) +118287*a(n-7) -202495*a(n-8) +284119*a(n-9) -331806*a(n-10) +326718*a(n-11) -273224*a(n-12) +193798*a(n-13) -115270*a(n-14) +56258*a(n-15) -21837*a(n-16) +6481*a(n-17) -1404*a(n-18) +210*a(n-19) -20*a(n-20) +a(n-21) for n>24

%e Some solutions for n=4

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

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

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

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

%Y Cf. A274858.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 09 2016