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Number of (n+2)X7 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
1

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

%S 17800,77618,267066,916658,3191760,11082632,38569884,134316050,

%T 467816690,1629405698,5667390680,19715419592,68594753068,238634097858,

%U 830238632478,2888535915458,10050627740076,34970754257408,121674300182928

%N Number of (n+2)X7 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 5 of A203923

%H R. H. Hardin, <a href="/A203920/b203920.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +2*a(n-3) +4*a(n-4) +24*a(n-5) -104*a(n-6) +366*a(n-7) +562*a(n-8) -1092*a(n-9) +892*a(n-10) +1032*a(n-11) -1064*a(n-12) -6270*a(n-13) +1420*a(n-14) +6282*a(n-15) -30476*a(n-16) +12300*a(n-17) +27280*a(n-18) -11250*a(n-19) +8350*a(n-20) -1500*a(n-21) -1000*a(n-22) +8125*a(n-24) -3125*a(n-25) for n>26

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 07 2012