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%I #13 May 03 2018 03:04:53
%S 4,0,3,1,11,23,123,101323373373
%N Repeatedly map numbers to the number of letters in the English name (include spaces, but no hyphens and no "and"s); sequence gives smallest nonnegative integer that needs exactly n iterations to get to 4.
%D M. Ecker, Number play, calculators, and card tricks: Mathemagical black holes, in E. Berlekamp and T. Rodgers, eds., The Mathemagician and Pied Puzzler: A Collection in Tribute to Martin Gardner, A. K. Peters, 1999, pp. 41-52.
%e Since "twenty three" has 12 letters (including the space), "twelve" has 6 letters, "three" has 5 letters, "four" has four letters, and no other smaller nonnegative integer maps to 4 in exactly 5 iterations, then a(5) = 23.
%Y Cf. A227290, A005589, A016037 (these do not count the spaces in the names of larger integers).
%K nonn,word,less
%O 0,1
%A _Matthew E. Coppenbarger_, Mar 20 2018
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