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A220935 T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..2 nXk array.

%I A220935 #5 Jul 23 2025 01:33:15
%S A220935 1,1,1,2,4,1,4,16,12,1,7,52,92,37,1,12,200,673,556,114,1,21,792,5912,
%T A220935 9107,3332,351,1,37,3080,48212,172904,123958,19996,1081,1,65,12164,
%U A220935 395844,2876430,4983202,1686304,119972,3329,1,114,47827,3232729,49406891
%N A220935 T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..2 nXk array.
%C A220935 Table starts
%C A220935 .1....1......2.......4.......7......12.......21......37....65.114
%C A220935 .1....4.....16......52.....200.....792.....3080...12164.47827
%C A220935 .1...12.....92.....673....5912...48212...395844.3232729
%C A220935 .1...37....556....9107..172904.2876430.49406891
%C A220935 .1..114...3332..123958.4983202
%C A220935 .1..351..19996.1686304
%C A220935 .1.1081.119972
%C A220935 .1.3329
%C A220935 .1
%e A220935 Some solutions for n=3 k=4
%e A220935 ..0..0..1..1....0..0..1..1....0..0..0..1....0..0..0..1....0..1..0..1
%e A220935 ..0..1..1..0....0..1..1..1....1..0..1..1....0..0..0..1....0..0..0..1
%e A220935 ..1..1..0..0....0..0..0..0....0..0..0..0....1..0..1..0....1..0..0..0
%Y A220935 Column 2 is A099098
%Y A220935 Row 1 is A005251(n+1)
%K A220935 nonn,tabl
%O A220935 1,4
%A A220935 _R. H. Hardin_ Dec 25 2012