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%I #21 Sep 04 2021 21:08:05
%S 5,10,12,13,31,38,43,49,51,55,59,60,76,83,85,97,117,118
%N Positions of 3's in A048288.
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/revfact.htm">Reversed Smarandache Concatenated Numbers, Prime factors from n down to 1</a>
%H M. Fleuren, <a href="http://www.gallup.unm.edu/~smarandache/michafleuren.htm">Factors and primes of Smarandache sequences</a>.
%H M. Fleuren, <a href="http://www.gallup.unm.edu/~smarandache/micha.txt">Smarandache Factors and Reverse factors</a>
%H Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_008.htm">Puzzle 8. Primes by Listing</a>, The Prime Puzzles and Problems Connection.
%Y Cf. A000422, A046462, A048288, A050679, A050681, A050682.
%K nonn,base,hard,less,more
%O 1,1
%A _Patrick De Geest_, Aug 15 1999
%E a(13)-a(16) from _Sean A. Irvine_, Aug 17 2021
%E Offset changed to 1 by and a(17)-a(18) from _Jinyuan Wang_, Sep 04 2021