A039940 - OEIS

%I #8 Apr 27 2017 18:42:37

%S 9,49,97,98,98,99,99,99,99,99,99,499,992,993,993,994,994,994,995,995,

%T 995,995,996,996,996,996,996,997,997,997,997,997,997,997,997,997,997,

%U 998,998,998,998,998,998,998,998,998,998,998,998,998,998,998,998,998

%N Smallest k for which k, 2k, ... nk all contain the digit 9.

%H Giovanni Resta, <a href="/A039940/b039940.txt">Table of n, a(n) for n = 1..10000</a>

%e a(11)=99 since 99, 198, 297, 396, 495, 594, 693, 792, 891, 990, and 1089 all contain a 9.

%Y Cf. A039932, A039933, A039934, A039935, A039936, A039937, A039938, A039939.

%K base,nonn

%O 1,1

%A _Erich Friedman_

%E More terms from _Patrick De Geest_, Oct 15 1999