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 A166755 #10 Dec 11 2024 17:17:39 %S A166755 0,12,106,1254,32426,2247486,443968782,255122769986,431534126902662, %T A166755 2165656440779563158,32418178732724142833570, %U A166755 1452876796004423753334759362,195482230310004930545348833858390,79131192890976439895988807925969458614,96533107106359142781127117074385161767893162 %N A166755 Number of n X n 1..2 arrays containing at least one of each value, and all equal values connected. %H A166755 Andrew Howroyd, <a href="/A166755/b166755.txt">Table of n, a(n) for n = 1..26</a> %F A166755 a(n) = 2*A068416(n). - _Andrew Howroyd_, Dec 11 2024 %e A166755 Some solutions for n=4 %e A166755 ...1.2.2.2...1.1.1.1...2.2.2.1...2.1.1.1...1.1.1.1...2.2.2.2...1.1.1.2 %e A166755 ...1.2.1.2...2.2.2.1...2.2.2.1...2.2.1.1...1.1.2.2...1.2.2.2...2.2.1.2 %e A166755 ...1.1.1.2...2.2.2.1...2.2.1.1...1.1.1.1...1.1.2.2...2.2.2.2...2.1.1.2 %e A166755 ...2.2.2.2...2.1.1.1...2.2.2.2...1.1.1.1...2.2.2.2...2.2.2.2...2.2.2.2 %e A166755 ------ %e A166755 ...1.1.1.2...2.1.1.1...2.2.2.2...1.1.1.1...1.1.1.1...1.1.1.1...2.2.2.2 %e A166755 ...1.1.2.2...2.1.1.1...2.2.1.2...1.1.1.1...2.2.1.1...1.2.1.2...1.2.2.2 %e A166755 ...1.1.1.2...2.2.1.1...2.2.1.2...1.1.2.1...1.2.1.1...1.2.2.2...1.1.2.2 %e A166755 ...1.1.2.2...2.2.2.2...2.1.1.1...2.2.2.1...1.1.1.1...1.1.1.2...1.1.1.2 %Y A166755 Cf. A068416. %K A166755 nonn %O A166755 1,2 %A A166755 _R. H. Hardin_, Oct 21 2009 %E A166755 a(7) onwards added using A068416 by _Andrew Howroyd_, Dec 11 2024