A203919 - OEIS

%I #5 Mar 31 2012 12:37:00

%S 5000,21632,75272,262088,916658,3220722,11309768,39783200,139846088,

%T 491348552,1725311282,6060344418,21285209138,74766898208,262625483282,

%U 922568228082,3240635377778,11383319836800,39985279887938

%N Number of (n+2)X6 0..1 arrays with every 3X3 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..1 introduced in row major order

%C Column 4 of A203923

%H R. H. Hardin, <a href="/A203919/b203919.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +4*a(n-2) +21*a(n-4) -44*a(n-5) +77*a(n-6) +158*a(n-7) -83*a(n-8) -645*a(n-9) +64*a(n-10) -2301*a(n-11) -3155*a(n-12) +1580*a(n-13) +6476*a(n-14) +55*a(n-15) +15516*a(n-16) +19296*a(n-17) -747*a(n-18) -810*a(n-19) -5913*a(n-20) -75627*a(n-21) -49815*a(n-22) +27054*a(n-23) -243*a(n-24) +19926*a(n-25) +11664*a(n-26) +10935*a(n-27) -6561*a(n-28) for n>29

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 07 2012