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Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum equal to the antidiagonal sum or central row sum equal to the central column sum
1

%I #4 Jun 14 2015 21:38:31

%S 576,1156,1936,4096,9216,17424,30976,66564,141376,264196,501264,

%T 1069156,2166784,4080400,8065600,16892100,33362176,63936016,128867904,

%U 264387600,516925696,1008570564,2044124944,4123951524,8059730176,15937042564

%N Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum equal to the antidiagonal sum or central row sum equal to the central column sum

%C Column 2 of A258921

%H R. H. Hardin, <a href="/A258919/b258919.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-2) +a(n-3) +14*a(n-4) -43*a(n-6) +3*a(n-7) -58*a(n-8) -44*a(n-9) +201*a(n-10) +33*a(n-11) +34*a(n-12) +42*a(n-13) -271*a(n-14) -191*a(n-15) -208*a(n-16) +352*a(n-17) +1001*a(n-18) +213*a(n-19) -574*a(n-20) -526*a(n-21) +129*a(n-22) -91*a(n-23) +66*a(n-24) +20*a(n-25) -7*a(n-26) +7*a(n-27) -a(n-28)

%e Some solutions for n=4

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

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

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

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

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

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

%Y Cf. A258921

%K nonn

%O 1,1

%A _R. H. Hardin_, Jun 14 2015