cp's OEIS Frontend

A166766 Number of n X 4 1..2 arrays containing at least one of each value, and all equal values connected.

%I A166766 #10 Dec 12 2024 14:53:30
%S A166766 6,56,292,1254,4942,18584,67756,241542,846502,2927816,10023380,
%T A166766 34042358,114900334,385933816,1291392908,4308452150,14341213590,
%U A166766 47651315192,158111069492,524063522870,1735584459598,5744207323976,19002070568572,62835884445574,207725012781046,686552300486040
%N A166766 Number of n X 4 1..2 arrays containing at least one of each value, and all equal values connected.
%H A166766 Andrew Howroyd, <a href="/A166766/b166766.txt">Table of n, a(n) for n = 1..200</a>
%H A166766 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (10,-37,59,-27,-25,21,5,-4,-1).
%F A166766 a(n) = 2*A378934(n). - _Andrew Howroyd_, Dec 12 2024
%e A166766 Some solutions for n=4
%e A166766 ...1.1.1.1...2.2.1.1...2.2.2.2...1.1.2.2...2.2.2.2...2.1.1.1...2.2.2.2
%e A166766 ...1.2.1.1...2.1.1.1...1.2.1.2...2.1.1.2...1.1.2.1...2.2.1.1...2.2.2.2
%e A166766 ...1.2.1.2...2.1.1.1...1.2.1.1...2.1.2.2...1.1.1.1...2.2.1.1...1.2.2.1
%e A166766 ...2.2.2.2...1.1.1.1...1.1.1.1...2.2.2.2...1.1.1.1...2.1.1.1...1.1.1.1
%e A166766 ------
%e A166766 ...2.2.2.2...2.2.2.2...2.2.1.1...1.1.2.1...2.1.1.1...1.1.1.1...1.1.2.2
%e A166766 ...2.1.1.1...1.1.1.2...1.2.2.1...1.1.2.1...2.1.2.2...1.2.1.2...1.1.1.1
%e A166766 ...1.1.1.1...1.1.2.2...1.2.1.1...1.1.1.1...2.1.2.2...1.2.2.2...1.1.1.1
%e A166766 ...1.1.1.1...2.2.2.2...1.1.1.1...1.1.1.1...2.2.2.2...1.1.2.2...1.1.1.1
%Y A166766 Twice row 4 of A378932.
%Y A166766 Cf. A378934.
%K A166766 nonn
%O A166766 1,1
%A A166766 _R. H. Hardin_, Oct 21 2009
%E A166766 a(16) onwards from _Andrew Howroyd_, Dec 12 2024