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A219075 Hilltop maps: number of nX5 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 nX5 array.

%I A219075 #6 Jul 23 2025 00:12:41
%S A219075 17,625,17537,494713,14228041,407374825,11660290321,333882416305,
%T A219075 9559854123673,273717397488937,7837125931615553,224393896465841065,
%U A219075 6424880595963477921,183958193843792111121,5267120030903659835073
%N A219075 Hilltop maps: number of nX5 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 nX5 array.
%C A219075 Column 5 of A219078
%H A219075 R. H. Hardin, <a href="/A219075/b219075.txt">Table of n, a(n) for n = 1..91</a>
%F A219075 Empirical: a(n) = 20*a(n-1) +158*a(n-2) +2330*a(n-3) +5837*a(n-4) +17850*a(n-5) -57426*a(n-6) -279582*a(n-7) -163347*a(n-8) +746554*a(n-9) +983888*a(n-10) -474072*a(n-11) -1651489*a(n-12) -646204*a(n-13) +913420*a(n-14) +1038852*a(n-15) +300209*a(n-16) -257176*a(n-17) -347922*a(n-18) -148694*a(n-19) +11843*a(n-20) -2590*a(n-21) +19366*a(n-22) -18694*a(n-23) +8067*a(n-24) -1302*a(n-25) -60*a(n-26) +180*a(n-27) -15*a(n-28)
%e A219075 Some solutions for n=3
%e A219075 ..0..1..1..1..1....0..1..1..1..1....0..0..1..1..0....0..1..1..1..1
%e A219075 ..0..1..0..1..0....0..1..0..1..0....1..1..0..0..1....0..1..1..1..0
%e A219075 ..1..0..0..1..1....0..1..0..1..1....1..0..0..1..0....0..1..1..0..0
%K A219075 nonn
%O A219075 1,1
%A A219075 _R. H. Hardin_ Nov 11 2012