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%I #4 Oct 25 2012 08:36:28
%S 1,3,3,7,15,7,15,63,63,15,31,255,511,255,31,61,1019,4091,4091,1019,61,
%T 121,4073,32739,65507,32739,4073,121,241,16289,261905,1048307,1048307,
%U 261905,16289,241,481,65153,2095233,16772877,33549827,16772877,2095233
%N T(n,k)=Hilltop maps: number of nXk binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or vertical neighbor in a random 0..4 nXk array
%C Table starts
%C ....1........3..........7............15.............31..............61
%C ....3.......15.........63...........255...........1019............4073
%C ....7.......63........511..........4091..........32739..........261905
%C ...15......255.......4091.........65507........1048307........16772877
%C ...31.....1019......32739.......1048307.......33549827......1073597617
%C ...61.....4073.....261905......16772877.....1073597617.....68710447465
%C ..121....16289....2095233.....268366049....34355128651...4397469258389
%C ..241....65153...16761837....4293856057..1099364046509.281438014358653
%C ..481...260609..134094563...68701687597.35179647135791
%C ..961..1042417.1072755573.1099226869621
%C .1921..4169595.8582037499
%C .3839.16678079
%H R. H. Hardin, <a href="/A218288/b218288.txt">Table of n, a(n) for n = 1..97</a>
%F Empirical: Column k=1 for an underlying 0..z array: a(n) = sum(i=1..2z+1){a(n-i)} z=1,2,3,4
%e Some solutions for n=3 k=4
%e ..0..1..1..1....1..0..0..1....1..0..0..0....0..0..0..0....0..1..1..0
%e ..1..1..0..1....0..1..0..1....1..0..0..1....1..1..0..1....0..0..1..1
%e ..0..1..1..1....0..1..0..1....1..1..0..0....1..1..1..0....1..0..0..0
%K nonn,tabl
%O 1,2
%A _R. H. Hardin_ Oct 25 2012
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