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A180765 Half the number of nX5 binary arrays with each element equal to at least one neighbor.

%I A180765 #5 Jul 22 2025 08:29:33
%S A180765 3,111,2385,52186,1154119,25448809,561487456,12387396391,273289411333,
%T A180765 6029284136868,133017439433103,2934617106201383,64743220889823228,
%U A180765 1428358285117311045,31512293679807784965,695220984328633501278
%N A180765 Half the number of nX5 binary arrays with each element equal to at least one neighbor.
%C A180765 Column 5 of A180771
%H A180765 R. H. Hardin, <a href="/A180765/b180765.txt">Table of n, a(n) for n=1..199</a>
%F A180765 Empirical: a(n) = 17*a(n-1) + 136*a(n-2) - 345*a(n-3) - 4373*a(n-4) + 71*a(n-5) + 66879*a(n-6) + 73663*a(n-7) - 605750*a(n-8) - 1149380*a(n-9) + 3440076*a(n-10) + 9495118*a(n-11) - 11523196*a(n-12) - 49881727*a(n-13) + 14883216*a(n-14) + 170573727*a(n-15) + 56476212*a(n-16) - 384039937*a(n-17) - 365812542*a(n-18) + 600541982*a(n-19) + 912782329*a(n-20) - 647992787*a(n-21) - 1217873627*a(n-22) + 831099316*a(n-23) + 509861969*a(n-24) - 535317645*a(n-25) - 243113473*a(n-26) + 146477582*a(n-27) + 239475023*a(n-28) - 56646215*a(n-29) - 153066695*a(n-30) + 13721643*a(n-31) + 55901473*a(n-32) + 8739700*a(n-33) - 17235985*a(n-34) - 7556526*a(n-35) + 4435220*a(n-36) + 2967912*a(n-37) - 742411*a(n-38) - 903018*a(n-39) + 68146*a(n-40) + 206458*a(n-41) + 20454*a(n-42) - 27768*a(n-43) - 10964*a(n-44) + 1696*a(n-45) + 1408*a(n-46)
%K A180765 nonn
%O A180765 1,1
%A A180765 _R. H. Hardin_ Sep 20 2010