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%I #16 Feb 19 2017 07:12:09
%S 1,8,10,19,91,801,802,1001,8001,8002,100001,800001,800002,1000000,
%T 9000000,9000001,11000000,19000000,19000001,80000000,90000000,
%U 90000001,800000000,900000000,900000001,8000000000,9000000000,9000000001,11000000000,19000000000,19000000001,80000000000,90000000000,90000000001
%N a(1) = 1; a(n) is the smallest natural number such that a(n) > a(n-1), and the name of a(n) in English starts with the letter a(n-1) ends with, and a(n) makes the sequence extendable.
%C "a(n) makes the sequence extendable" means the name of a(n) does not end with any of the letters r, x, y and d.
%e If a(5) were 90 (ninety, which ends with y), it would make the sequence finite. Therefore, a(5) has to be 91.
%Y Cf. A277971, A277972, A281068.
%K easy,nonn,word
%O 1,2
%A _Ivan N. Ianakiev_, Jan 14 2017