a(n) = least k such that the remainder when 20^k is divided by k is n.
19, 3, 17, 6, 15, 7, 13, 9, 11, 18, 7989, 92, 973, 33, 611, 24, 2661, 382, 559, 21
4 seqfan posts
Tue Aug 11 01:35:14 CEST 2009 [seqfan] Re: Dead b-files for A127816 and others
Wed Aug 5 19:56:50 CEST 2009 [seqfan] Re: Several errors in A128172
Wed Aug 5 07:33:41 CEST 2009 [seqfan] Re: Several errors in A128172
Tue Aug 4 21:23:49 CEST 2009 [seqfan] Several errors in A128172
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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