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 A034048 Numbers with multiplicative digital root value 0. 17
 0, 10, 20, 25, 30, 40, 45, 50, 52, 54, 55, 56, 58, 59, 60, 65, 69, 70, 78, 80, 85, 87, 90, 95, 96, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 120, 125, 130, 140, 145, 150, 152, 154, 155, 156, 158, 159, 160, 165, 169, 170, 178, 180, 185, 187, 190, 195 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numbers with root value 1 are the 'repunits' (see A000042). This sequence has density 1. - Franklin T. Adams-Watters, Apr 01 2009 Any integer with at least one 0 among its base 10 digits is in this sequence. - Alonso del Arte, Aug 29 2014 This sequence is 10-automatic: it contains numbers with a 0, or with a 5 and any even digit. - Charles R Greathouse IV, Feb 13 2017 LINKS Franklin T. Adams-Watters, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Multiplicative Digital Root EXAMPLE 20 is in the sequence because 2 * 0 = 0. 25 is in the sequence because 2 * 5 = 10 and 1 * 0 = 0. MATHEMATICA mdr0Q[n_]:=NestWhile[Times@@IntegerDigits[#]&, n, #>9&]==0; Select[Range[ 0, 200], mdr0Q] (* Harvey P. Dale, Jul 21 2020 *) PROG (PARI) is(n)=factorback(digits(n))==0 \\ Charles R Greathouse IV, Feb 13 2017 CROSSREFS Cf. A031347, A034048, A002275, A034049, A034050, A034051, A034052, A034053, A034054, A034055, A034056 (numbers having multiplicative digital roots 0-9). Cf. the subsets A011540 and A008592. Sequence in context: A098165 A104801 A144140 * A199978 A342142 A179819 Adjacent sequences:  A034045 A034046 A034047 * A034049 A034050 A034051 KEYWORD nonn,base,easy AUTHOR Patrick De Geest, Sep 15 1998 STATUS approved

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Last modified April 12 09:39 EDT 2021. Contains 342920 sequences. (Running on oeis4.)