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%I #10 Apr 13 2024 22:52:47
%S 9,9,9,9,9,9,9,9,9,8,9,9,9,9,9,9,9,9,9,8,9,9,9,9,9,9,9,9,9,8,9,9,9,9,
%T 9,9,9,9,9,8,9,9,9,9,9,9,9,9,9,8,9,9,9,9,9,9,9,9,9,8,9,9,9,9,9,9,9,9,
%U 9,8,9,9,9,9,9,9,9,9,9,8,9,9,9,9,9,9,9,9,9,7,8,8,8,8,8,8,8,8,7,8,9,9,9,9,9
%N Greatest digit not used in n (or 10 if n is pandigital).
%C a(A050278(1)) = a(1023456789) = 10, the first term with that value, as 1023456789 is the first base 10 pandigital number.
%H Alois P. Heinz, <a href="/A116667/b116667.txt">Table of n, a(n) for n = 0..10000</a>
%e a(89) = 7 because decimal digits 8 and 9 are both used in 89.
%o (Python)
%o def A116667(n):
%o s = set(str(n))
%o for i in range(9,-1,-1):
%o if str(i) not in s:
%o return i
%o return 10 # _Chai Wah Wu_, Apr 13 2024
%Y Cf. A067898 (least digit not used in n), A050278 (pandigital numbers).
%K base,easy,nonn
%O 0,1
%A _Rick L. Shepherd_, Feb 22 2006