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A240786 Number of 5Xn 0..1 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..1 introduced in row major order.

%I A240786 #6 Jul 23 2025 11:07:37
%S A240786 16,111,459,2167,10150,47920,226532,1071982,5074441,24028807,
%T A240786 113785341,538857251,2551907524,12085420318,57234822524,271056496272,
%U A240786 1283688860005,6079388685605,28791225250367,136351659911471,645744522623364
%N A240786 Number of 5Xn 0..1 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..1 introduced in row major order.
%C A240786 Row 5 of A240783
%H A240786 R. H. Hardin, <a href="/A240786/b240786.txt">Table of n, a(n) for n = 1..210</a>
%F A240786 Empirical: a(n) = 10*a(n-1) -35*a(n-2) +50*a(n-3) +23*a(n-4) -204*a(n-5) +114*a(n-6) +684*a(n-7) -1284*a(n-8) -309*a(n-9) +4412*a(n-10) -5481*a(n-11) -90*a(n-12) +4826*a(n-13) -3964*a(n-14) -3408*a(n-15) +3143*a(n-16) +3475*a(n-17) -3191*a(n-18) +7943*a(n-19) +2119*a(n-20) +1380*a(n-21) -8241*a(n-22) -8523*a(n-23) +3733*a(n-24) -79*a(n-25) +1925*a(n-26) +1275*a(n-27) +131*a(n-28) -147*a(n-29) -286*a(n-30) for n>34
%e A240786 Some solutions for n=4
%e A240786 ..0..1..0..1....0..1..0..1....0..1..1..0....0..0..1..0....0..1..1..0
%e A240786 ..1..0..0..1....1..1..0..0....1..1..1..0....0..0..1..1....0..1..1..1
%e A240786 ..0..0..1..1....1..0..1..0....1..1..1..0....0..0..1..1....1..0..1..1
%e A240786 ..0..0..1..1....0..1..0..1....1..1..1..0....1..0..1..0....1..0..0..1
%e A240786 ..0..1..0..1....1..0..1..0....0..1..1..0....1..0..1..0....1..0..0..1
%K A240786 nonn
%O A240786 1,1
%A A240786 _R. H. Hardin_, Apr 12 2014