%I #28 May 03 2019 07:21:25
%S 1,0,1,1,11,44,169,588,1948,6560,23133,84565,317755,1198336,4509419,
%T 16909184,63409935,238609052,902444517,3429249843,13076666409,
%U 49977802752,191312873561,733365845820,2815437297416,10825960652800,41694907460224,160823207301705
%N Number of 4-ary Lyndon words whose trace and subtrace are both 0 mod 4.
%C The trace of a word is the sum of its characters; the subtrace of a word is the sum of all products of pairs of its characters.
%H Max Alekseyev, <a href="http://home.gwu.edu/~maxal/gpscripts/">PARI/GP scripts for miscellaneous math problems</a>
%H F. Ruskey, <a href="http://combos.org/TSlyndonZ4">4-ary Lyndon words with given trace and subtrace</a>
%Y Cf. A074403, A074404, A074405, A074406, A074407, A074408, A074409, A074410, A074411, A074412, A074413.
%K nonn
%O 1,5
%A _Frank Ruskey_, Mar 28 2002
%E Terms a(15) onward from _Max Alekseyev_, Apr 09 2013
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