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A222445 Sum of neighbor maps: number of nX2 binary arrays indicating the locations of corresponding elements equal to the sum mod 4 of their horizontal, vertical and antidiagonal neighbors in a random 0..3 nX2 array.

%I A222445 #7 Jul 23 2025 02:35:51
%S A222445 2,14,64,210,1024,4000,16288,65536,260080,1048576,4191744,16774656,
%T A222445 67108864,268379104,1073741824,4294909952,17179811840,68719476736,
%U A222445 274876642816,1099511627776,4398045331456,17592184864768,70368744177664
%N A222445 Sum of neighbor maps: number of nX2 binary arrays indicating the locations of corresponding elements equal to the sum mod 4 of their horizontal, vertical and antidiagonal neighbors in a random 0..3 nX2 array.
%C A222445 Column 2 of A222448
%H A222445 R. H. Hardin, <a href="/A222445/b222445.txt">Table of n, a(n) for n = 1..210</a>
%F A222445 Empirical: a(n) = 4*a(n-1) +60*a(n-5) -240*a(n-6) -1456*a(n-10) +5824*a(n-11) +18496*a(n-15) -73984*a(n-16) -133120*a(n-20) +532480*a(n-21) +544768*a(n-25) -2179072*a(n-26) -1179648*a(n-30) +4718592*a(n-31) +1048576*a(n-35) -4194304*a(n-36)
%e A222445 Some solutions for n=3
%e A222445 ..1..1....1..1....0..0....0..1....1..0....1..0....1..0....1..0....0..0....1..1
%e A222445 ..1..1....1..1....0..0....0..1....0..0....0..1....1..1....1..1....0..0....0..0
%e A222445 ..0..0....1..0....0..1....0..0....1..1....0..1....0..0....0..1....1..1....1..0
%K A222445 nonn
%O A222445 1,1
%A A222445 _R. H. Hardin_ Feb 20 2013