%I #12 Jun 17 2019 07:30:45
%S 1,4,3,8,18,47,108,268,638,1553,3761,9189,22453,55185,135894,335906,
%T 832312,2068066,5149845,12852750,32138353,80509495,202013368,
%U 507669048,1277586867,3219366610,8122275225
%N Smooth Lyndon words with 4 colors.
%C We call a Lyndon word (x[1],x[2],...,x[n]) smooth if abs(x[k]-x[k-1]) <= 1 for 2<=k<=n.
%e (See A215329).
%Y Cf. A215329 (smooth necklaces, 4 colors), A215328 (smooth Lyndon words, 3 colors).
%K nonn,more
%O 0,2
%A _Joerg Arndt_, Aug 08 2012
%E More terms from _Joerg Arndt_, Jun 17 2019