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%I #14 Apr 23 2023 07:28:03
%S 6,11,23,323,1103323373373373373373373373373
%N a(1) = 6; thereafter a(n) = smallest number with a(n-1) letters in American English.
%C a(5) should be findable, but a(6) will probably not be well defined.
%C See A362441 for a British English version.
%D GCHQ, The GCHQ Puzzle Book, Penguin, 2016. See pages 92 and 275.
%F a(n) = A080777(a(n-1)) for n > 1. - _Michael S. Branicky_, Apr 22 2023
%e a(2) = 11 since "eleven" is the smallest number with 6 letters.
%e a(3) = 23 since "twenty three" is the smallest with 11 letters.
%Y Cf. A005589, A362123, A362441.
%K nonn,word,more
%O 1,1
%A _N. J. A. Sloane_, Apr 22 2023
%E a(5) from _Michael S. Branicky_, Apr 22 2023 using A080777