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%I #14 Nov 01 2022 12:14:02
%S 1,9,19,99,119,199,999,1199,1999,9999,19999,99999,119999,199999,
%T 999999,1199999,1999999,9999999,19999999,99999999,119999999,199999999,
%U 999999999,1199999999,1999999999,9999999999,19999999999,99999999999,119999999999,199999999999,999999999999
%N a(n) is the smallest number k such that the letter "N" appears n times when k is written in English.
%D Rodolfo Kurchan, Mesmerizing Math Puzzles, Sterling Publications, p. 19.
%e a(2) = 9 because "NiNe" has 2 N's.
%K nonn,word
%O 1,2
%A _Rodolfo Kurchan_, Mar 20 2001
%E Edited by _Jon E. Schoenfield_, Sep 29 2018
%E a(9)-a(19) from _Sean A. Irvine_, Oct 31 2022
%E a(20) and beyond from _Michael S. Branicky_, Nov 01 2022