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 A201991 Smallest palindrome which has multiplicative persistence n. 1
 0, 11, 44, 55, 77, 868, 69996, 2683862, 6783876, 268969862, 37889398873, 477788989887774 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Probably finite. LINKS Eric Weisstein's World of Mathematics, Multiplicative Persistence EXAMPLE 0 has persistence 0. 11 -> 1 has persistence 1. 44 -> 16 -> 6 has persistence 2. 55 -> 25 -> 10 -> 0 has persistence 3. 77 -> 49 -> 36 -> 18 -> 8 has persistence 4. 868 -> 384 -> 96 -> 54 -> 20 -> 0 has persistence 5. MATHEMATICA lst = {}; int[n_] := IntegerDigits[n]; n = 0; Do[While[True, s = Length@int[n]; r = PadRight[int[n], 2*s, Reverse@int[n]]; If[s > 1, r = Drop[r, {s}]]; p = k = FromDigits[r]; c = 0; While[k > 9, k = Times @@ int[k]; c++]; If[c == l, Break[]]; n++]; AppendTo[lst, p], {l, 0, 10}]; lst (* Arkadiusz Wesolowski, Jul 05 2012 *) CROSSREFS Cf. A031346, A003001, A002113. Sequence in context: A259798 A239266 A259963 * A010819 A022703 A061976 Adjacent sequences:  A201988 A201989 A201990 * A201992 A201993 A201994 KEYWORD nonn,base,fini,nice AUTHOR Arkadiusz Wesolowski, Dec 07 2011 STATUS approved

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Last modified October 21 07:01 EDT 2019. Contains 328292 sequences. (Running on oeis4.)