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