cp's OEIS Frontend

A039932 Smallest number k for which k, 2k, ... nk all contain the digit 1.

%I A039932 #13 Feb 21 2021 14:03:44
%S A039932 1,51,51,531,2571,2571,2571,15703,15703,15703,15703,15703,15703,15703,
%T A039932 90271,90271,90271,90271,90271,90271,90271,90271,102053,530102,530102,
%U A039932 530102,530102,530102,530102,530102,530102,530102,530102,530102,530102
%N A039932 Smallest number k for which k, 2k, ... nk all contain the digit 1.
%C A039932 There are relatively few distinct terms in this sequence. The following list shows the frequencies of a(n) for n=1..2443. - _Georg Fischer_, Feb 21 2021
%C A039932       1 1
%C A039932       2 51
%C A039932       1 531
%C A039932       3 2571
%C A039932       7 15703
%C A039932       8 90271
%C A039932       1 102053
%C A039932      15 530102
%C A039932       5 4550102
%C A039932       1 4570102
%C A039932       4 4580102
%C A039932      49 22900501
%C A039932      53 134003006
%C A039932      93 1002003005
%C A039932     200 5001002003
%C A039932       1 5003001002
%C A039932     223 30005001002
%C A039932       1 30005002001
%C A039932     576 200030005001
%C A039932    1199 1000200030005
%H A039932 Giovanni Resta, <a href="/A039932/b039932.txt">Table of n, a(n) for n = 1..2443</a>
%e A039932 a(3)=51 since 51, 102, and 153 all contain a 1.
%Y A039932 Cf. A039933, A039934, A039935, A039936, A039937, A039938, A039939, A039940.
%K A039932 nonn,base
%O A039932 1,2
%A A039932 _Erich Friedman_
%E A039932 More terms from _Patrick De Geest_, Oct 15 1999