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A221446 T(n,k)=Hilltop maps: number of nXk binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..1 nXk array.

%I A221446 #6 Jul 23 2025 01:56:23
%S A221446 1,3,1,5,9,1,9,33,31,1,17,117,221,105,1,31,429,1465,1473,355,1,57,
%T A221446 1577,10593,18393,9829,1201,1,105,5785,76055,260557,230845,65569,4063,
%U A221446 1,193,21217,543081,3669101,6415089,2897357,437437,13745,1,355,77825,3883061
%N A221446 T(n,k)=Hilltop maps: number of nXk binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..1 nXk array.
%C A221446 Table starts
%C A221446 .1.......3..........5..............9................17....................31
%C A221446 .1.......9.........33............117...............429..................1577
%C A221446 .1......31........221...........1465.............10593.................76055
%C A221446 .1.....105.......1473..........18393............260557...............3669101
%C A221446 .1.....355.......9829.........230845...........6415089.............177320895
%C A221446 .1....1201......65569........2897357.........157933741............8569227073
%C A221446 .1....4063.....437437.......36364977........3888200065..........414116287743
%C A221446 .1...13745....2918273......456419681.......95724317069........20012580804813
%C A221446 .1...46499...19468741.....5728560373.....2356654610641.......967127817426727
%C A221446 .1..157305..129882145....71899621813....58018914711981.....46737411242830049
%C A221446 .1..532159..866485149...902417942313..1428378365629601...2258631763028702151
%C A221446 .1.1800281.5780598081.11326320232169.35165510520296269.109150620595639469645
%H A221446 R. H. Hardin, <a href="/A221446/b221446.txt">Table of n, a(n) for n = 1..217</a>
%e A221446 Some solutions for n=3 k=4
%e A221446 ..1..0..1..1....0..1..1..1....1..1..1..0....1..1..0..1....1..0..0..0
%e A221446 ..1..0..1..1....0..1..1..0....0..0..1..0....1..1..1..1....1..1..1..1
%e A221446 ..0..1..0..1....1..1..1..0....1..0..0..1....1..1..1..0....1..1..1..0
%Y A221446 Row 1 is A000213(n+1)
%K A221446 nonn,tabl
%O A221446 1,2
%A A221446 _R. H. Hardin_ Jan 17 2013