A253037 - OEIS

%I #4 Dec 26 2014 12:53:53

%S 130,341,928,2638,7608,22304,65765,195277,582025,1739571,5208638,

%T 15614748,46850138,140636244,422341551,1268587807,3811207227,

%U 11450967363,34408283600,103394858790,310709678538,933719999422,2806003978481

%N Number of (n+2)X(1+2) 0..3 arrays with every consecutive three elements in every row, column, diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order

%C Column 1 of A253044

%H R. H. Hardin, <a href="/A253037/b253037.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) +8*a(n-2) -32*a(n-3) -49*a(n-4) +35*a(n-5) +388*a(n-6) +333*a(n-7) -1470*a(n-8) -2015*a(n-9) +1827*a(n-10) +7705*a(n-11) +2724*a(n-12) -22079*a(n-13) -17133*a(n-14) +43082*a(n-15) +66963*a(n-16) -35868*a(n-17) -207245*a(n-18) -79740*a(n-19) +352817*a(n-20) +377343*a(n-21) -206023*a(n-22) -735286*a(n-23) -244312*a(n-24) +744588*a(n-25) +589880*a(n-26) -341664*a(n-27) -577644*a(n-28) +32392*a(n-29) +309128*a(n-30) +20704*a(n-31) -83712*a(n-32) -4480*a(n-33) +8832*a(n-34) for n>35

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 26 2014