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A279489 Number of nX3 0..1 arrays with no element equal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

%I A279489 #4 Dec 13 2016 12:18:33
%S A279489 0,5,38,254,1433,8330,46095,250440,1332366,6989712,36235705,185945098,
%T A279489 945895078,4775688338,23953618305,119447804293,592560152936,
%U A279489 2925941530150,14387128139448,70473511001771,344006151796898
%N A279489 Number of nX3 0..1 arrays with no element equal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
%C A279489 Column 3 of A279494.
%H A279489 R. H. Hardin, <a href="/A279489/b279489.txt">Table of n, a(n) for n = 1..210</a>
%F A279489 Empirical: a(n) = 15*a(n-1) -87*a(n-2) +272*a(n-3) -624*a(n-4) +1167*a(n-5) -1375*a(n-6) +1464*a(n-7) -789*a(n-8) -1362*a(n-9) +1821*a(n-10) -5907*a(n-11) +6610*a(n-12) -315*a(n-13) +3501*a(n-14) +12667*a(n-15) -11622*a(n-16) -6744*a(n-17) -25975*a(n-18) -15276*a(n-19) +19746*a(n-20) +18848*a(n-21) +81336*a(n-22) +55014*a(n-23) -70070*a(n-24) -112530*a(n-25) -108033*a(n-26) -52409*a(n-27) +49242*a(n-28) +227127*a(n-29) +332239*a(n-30) +11925*a(n-31) -374757*a(n-32) -309097*a(n-33) -114708*a(n-34) -22170*a(n-35) +258011*a(n-36) +537372*a(n-37) +265353*a(n-38) -363395*a(n-39) -575142*a(n-40) -183579*a(n-41) +249255*a(n-42) +295275*a(n-43) +86565*a(n-44) -70251*a(n-45) -81003*a(n-46) -30351*a(n-47) +3177*a(n-48) +9021*a(n-49) +4779*a(n-50) +1403*a(n-51) +246*a(n-52) +24*a(n-53) +a(n-54) for n>55
%e A279489 Some solutions for n=4
%e A279489 ..0..0..0. .0..1..0. .0..0..1. .0..1..1. .0..1..0. .0..1..1. .0..1..1
%e A279489 ..1..0..1. .1..1..0. .0..1..0. .0..0..0. .0..1..0. .0..1..0. .1..0..0
%e A279489 ..1..1..0. .0..0..1. .1..0..0. .0..1..0. .1..0..1. .1..1..0. .1..1..0
%e A279489 ..0..0..1. .0..0..1. .1..1..1. .1..1..0. .0..0..0. .0..0..1. .1..1..0
%Y A279489 Cf. A279494.
%K A279489 nonn
%O A279489 1,2
%A A279489 _R. H. Hardin_, Dec 13 2016