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A252009 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum 1 3 6 or 8 and every diagonal and antidiagonal sum not 1 3 6 or 8 1

%I

%S 1168,1602,1406,2002,3128,4570,6562,10980,18568,26866,47386,84660,

%T 122946,224610,409428,595934,1099500,2017128,2940062,5447180,10020972,

%U 14609852,27109394,49938584,72814596,135212590,249247170,363421408,675111432

%N Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum 1 3 6 or 8 and every diagonal and antidiagonal sum not 1 3 6 or 8

%C Column 2 of A252015

%H R. H. Hardin, <a href="/A252009/b252009.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 9*a(n-3) +a(n-5) -22*a(n-6) -9*a(n-8) +6*a(n-9) +23*a(n-11) +23*a(n-12) -15*a(n-14) -15*a(n-15) for n>22

%e Some solutions for n=4

%e ..0..0..3..3....0..3..0..3....1..0..2..1....2..1..3..2....0..2..1..0

%e ..0..1..2..3....3..2..1..0....2..2..2..2....1..1..1..1....2..2..2..2

%e ..3..2..1..0....0..1..2..3....0..1..2..0....3..1..2..3....1..2..3..1

%e ..0..0..3..3....3..3..0..0....1..0..2..1....2..1..3..2....0..2..1..0

%e ..3..1..2..0....0..2..1..3....2..2..2..2....1..1..1..1....2..2..2..2

%e ..0..0..3..3....0..3..0..3....3..1..2..0....3..1..2..0....1..2..0..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 12 2014

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Last modified June 26 10:00 EDT 2022. Contains 354879 sequences. (Running on oeis4.)