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A232020 Number of nX5 0..2 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors.

%I A232020 #6 Jul 23 2025 06:47:58
%S A232020 51,716,52680,3668759,266779524,19227454407,1386576216443,
%T A232020 100026008988909,7214505515214571,520380715850845302,
%U A232020 37534653006701646356,2707344505456485382130,195278730937825588935157
%N A232020 Number of nX5 0..2 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors.
%C A232020 Column 5 of A232023
%H A232020 R. H. Hardin, <a href="/A232020/b232020.txt">Table of n, a(n) for n = 1..210</a>
%F A232020 Empirical: a(n) = 51*a(n-1) +1709*a(n-2) -3322*a(n-3) -709171*a(n-4) -2253929*a(n-5) +87204864*a(n-6) +438193140*a(n-7) -5083075630*a(n-8) -21508462382*a(n-9) +126850541368*a(n-10) +406583965722*a(n-11) -1654793760869*a(n-12) -3605448973767*a(n-13) +12973680473891*a(n-14) +18876214872304*a(n-15) -70565885486364*a(n-16) -93710907270316*a(n-17) +270652747878947*a(n-18) +384062407194770*a(n-19) -420281252224531*a(n-20) -716290299119857*a(n-21) -266277634901151*a(n-22) +2127547571495*a(n-23) +377201492733031*a(n-24) +276656861200522*a(n-25) -68333741627600*a(n-26) -14328379159582*a(n-27) -49672744631068*a(n-28) -68111539250695*a(n-29) +25054413840127*a(n-30) +16739714021218*a(n-31) -3993304936259*a(n-32) +2872789395548*a(n-33) -93742451004*a(n-34) -1672268758969*a(n-35) +131609119929*a(n-36) +279643304785*a(n-37) -19537641382*a(n-38) -23945224836*a(n-39) +1053476640*a(n-40) +898919424*a(n-41) for n>42
%e A232020 Some solutions for n=3
%e A232020 ..0..0..0..0..0....0..0..0..0..0....2..2..0..0..0....0..0..1..2..2
%e A232020 ..1..0..0..1..2....2..2..1..0..0....2..0..0..0..1....0..1..2..2..0
%e A232020 ..2..2..1..1..1....2..2..1..1..2....1..2..2..2..2....0..0..0..0..2
%K A232020 nonn
%O A232020 1,1
%A A232020 _R. H. Hardin_, Nov 17 2013