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 A198377 Smallest nonprime number with multiplicative persistence n. 0
 0, 10, 25, 39, 77, 679, 6788, 68889, 2677889, 26888999, 3778889989, 277777788888899 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS 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. LINKS EXAMPLE For n=4, a(4) = 39 because 39 is the smallest nonprime number with multiplicative persistence 3: 39 -> 27 -> 14 -> 4. CROSSREFS Cf. A046500 (smallest prime with multiplicative persistence n). Sequence in context: A087473 A014120 A003001 * A038350 A003344 A047721 Adjacent sequences:  A198374 A198375 A198376 * A198378 A198379 A198380 KEYWORD nonn,base AUTHOR Jaroslav Krizek, Oct 23 2011 STATUS approved

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Last modified August 14 17:44 EDT 2018. Contains 313751 sequences. (Running on oeis4.)