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 A046500 Smallest prime with multiplicative persistence n. 11
 2, 11, 29, 47, 277, 769, 8867, 186889, 2678789, 26899889, 3778888999, 277777788888989 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS The persistence of a number is the number of times you need to multiply the digits together before reaching a single digit. LINKS Table of n, a(n) for n=0..11. C. Rivera, Puzzle page N. J. A. Sloane, The persistence of a number, J. Recreational Math., 6 (1973), 97-98. Eric Weisstein's World of Mathematics, Multiplicative Persistence. EXAMPLE 47 -> 28 -> 16 -> 6 has persistence 3. MATHEMATICA a[n_]:=Length[NestWhileList[Times@@IntegerDigits[#]&, n, #>9&]]-1; t={}; i=1; Do[While[a[p=Prime[i]]!=n, i++]; AppendTo[t, p], {n, 0, 9}]; t (* Jayanta Basu, Jun 02 2013 *) CROSSREFS Cf. A003001, A014120. Sequence in context: A136317 A090389 A061238 * A062123 A345213 A117560 Adjacent sequences: A046497 A046498 A046499 * A046501 A046502 A046503 KEYWORD nonn,base,more,hard,nice AUTHOR Patrick De Geest, Sep 15 1998 EXTENSIONS Value for n=10 and n=11 found by Jud McCranie STATUS approved

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Last modified August 7 03:07 EDT 2024. Contains 375003 sequences. (Running on oeis4.)