This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A188519 #7 Jul 22 2025 11:15:08 %S A188519 20,400,4143,40230,342240,2800798,22015314,169875850,1291198707, %T A188519 9730141740,72859323174,543367409130,4040626627139,29988912453443, %U A188519 222268109960222,1645817547627269,12178540896840119,90075084742836021 %N A188519 Number of nX5 binary arrays without the pattern 1 1 0 diagonally, vertically or horizontally. %C A188519 Column 5 of A188523 %H A188519 R. H. Hardin, <a href="/A188519/b188519.txt">Table of n, a(n) for n = 1..200</a> %F A188519 Empirical: a(n)=14*a(n-1)+12*a(n-2)-869*a(n-3)+1315*a(n-4)+25339*a(n-5)-55704*a(n-6)-466536*a(n-7)+1104069*a(n-8)+6123144*a(n-9)-13871452*a(n-10)-60905308*a(n-11)+122840856*a(n-12)+473902055*a(n-13)-810705818*a(n-14)-2932504534*a(n-15)+4131855019*a(n-16)+14571427067*a(n-17)-16696287227*a(n-18)-58561243631*a(n-19)+54702515236*a(n-20)+191588731358*a(n-21)-148452953569*a(n-22)-513291220886*a(n-23)+340859242431*a(n-24)+1131765472611*a(n-25)-675017422947*a(n-26)-2060462245934*a(n-27)+1167999276063*a(n-28)+3099080394556*a(n-29)-1770250494282*a(n-30)-3837665043366*a(n-31)+2329323672403*a(n-32)+3875748540760*a(n-33)-2614929879690*a(n-34)-3130743870873*a(n-35)+2448428133991*a(n-36)+1944185589624*a(n-37)-1860043238075*a(n-38)-842724478681*a(n-39)+1103495474142*a(n-40)+167817486381*a(n-41)-476717517573*a(n-42)+78582422599*a(n-43)+121853141835*a(n-44)-91254459222*a(n-45)+5768288867*a(n-46)+46035625299*a(n-47)-22656845337*a(n-48)-15248405057*a(n-49)+12059870046*a(n-50)+3756383370*a(n-51)-3920799304*a(n-52)-833927678*a(n-53)+900771854*a(n-54)+215654330*a(n-55)-155066412*a(n-56)-61762189*a(n-57)+21214719*a(n-58)+15278566*a(n-59)-2522154*a(n-60)-2885183*a(n-61)+283792*a(n-62)+399816*a(n-63)-29377*a(n-64)-39473*a(n-65)+2394*a(n-66)+2636*a(n-67)-125*a(n-68)-107*a(n-69)+3*a(n-70)+2*a(n-71) %e A188519 Some solutions for 3X5 %e A188519 ..0..1..0..0..1....0..1..0..1..1....1..0..1..0..1....0..1..0..1..0 %e A188519 ..1..0..0..0..1....0..0..0..0..1....0..0..0..0..0....0..1..0..0..0 %e A188519 ..0..0..0..0..1....0..0..1..1..1....1..0..1..1..1....1..1..1..1..1 %K A188519 nonn %O A188519 1,1 %A A188519 _R. H. Hardin_ Apr 02 2011