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Number of Lyndon words (aperiodic necklaces) with 4n beads of 4 colors, n beads of each color.
3

%I #10 Oct 21 2021 10:48:36

%S 1,6,312,30798,3941280,586637250,96197630040,16875655269942,

%T 3111284137104000,595909785174026400,117634021776545937000,

%U 23797087019979071174574,4912693780461256332795168,1031629572413246016139181538,219809927417367517614451764984

%N Number of Lyndon words (aperiodic necklaces) with 4n beads of 4 colors, n beads of each color.

%H <a href="/index/Lu#Lyndon">Index entries for sequences related to Lyndon words</a>

%F 1/(4n) * sum over d|n of {mu(n/d) * (4d)! / d!^4}.

%e For n=1 the 6 words are 0123 0132 0213 0231 0312 0321 . - _R. J. Mathar_, Oct 21 2021

%Y a(n)=A029809(n)*6. a(n) = A074652(n)/4.

%K nonn

%O 0,2

%A _Christian G. Bower_, Aug 29 2002

%E a(0)=1 prepended by _Alois P. Heinz_, Aug 24 2015