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%I #9 Mar 30 2012 19:00:25
%S 0,10,25,39,77,679,6788,68889,2677889,26888999,3778889989,
%T 277777788888899
%N Smallest nonprime number with multiplicative persistence n.
%C Probably finite sequence. The multiplicative persistence of a number is the number of times you need to multiply the digits together before reaching a single digit.
%e For n=4, a(4) = 39 because 39 is the smallest nonprime number with multiplicative persistence 3: 39 -> 27 -> 14 -> 4.
%Y Cf. A046500 (smallest prime with multiplicative persistence n).
%K nonn,base
%O 0,2
%A _Jaroslav Krizek_, Oct 23 2011
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