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 A034051 Numbers with multiplicative digital root value 4. 18
 4, 14, 22, 27, 39, 41, 72, 89, 93, 98, 114, 122, 127, 139, 141, 172, 189, 193, 198, 212, 217, 221, 249, 266, 271, 277, 294, 319, 333, 338, 346, 364, 379, 383, 391, 397, 411, 429, 436, 463, 492, 626, 634, 643, 662, 677, 712, 721, 727, 739, 767, 772, 776, 793 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..5000 Eric Weisstein's World of Mathematics, Multiplicative Digital Root MAPLE mdr:= proc(n) option remember; if n < 10 then return(n) fi; procname(convert(convert(n, base, 10), `*`)) end proc: select(mdr=4, [\$1..10^5]); # Robert Israel, Oct 19 2015 MATHEMATICA Select[Range@ 800, FixedPoint[Times @@ IntegerDigits@ # &, #] == 4 &] (* Michael De Vlieger, Oct 19 2015 *) PROG (PARI) t(n) = {while(n>9, n=prod(i=1, #n=digits(n), n[i])); n}; for(n=0, 1e4, if(t(n) == 4, print1(n", "))); \\ Altug Alkan, Oct 19 2015 CROSSREFS Cf. A031347. Cf. A034048, A002275, A034049, A034050, A034051, A034052, A034053, A034054, A034055, A034056 (numbers having multiplicative digital roots 0-9). Sequence in context: A165721 A197638 A051806 * A199984 A044437 A298008 Adjacent sequences:  A034048 A034049 A034050 * A034052 A034053 A034054 KEYWORD nonn,base,easy AUTHOR Patrick De Geest, Sep 15 1998 EXTENSIONS Incorrect formula removed by Martin Renner, Oct 19 2015 STATUS approved

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Last modified December 11 12:52 EST 2018. Contains 318049 sequences. (Running on oeis4.)