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%I #26 Oct 21 2021 13:10:34
%S 1,2,2,3,4,5,7,10,14,21,31,45,66,99
%N Length of shortest word of frequency depth n.
%C The frequency depth of a word is the number of times one must take the multiset of multiplicities to reach the singleton (1), without rearranging it.
%C For example, the word (11213331) has frequency depth 7: (11213331) -> (21131) -> (1211) -> (112) -> (21) -> (11) -> (2) -> (1).
%e The shortest words of frequency depth 10 are of the form (112122112112122122112) and (112122122112112122112), up to substitution and reflection.
%Y Cf. A011784.
%K nonn,hard,more
%O 1,2
%A _Ludovic Schwob_, Sep 21 2019
%E Incorrect terms removed by _Samuel B. Reid_, Aug 25 2021