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A201020 Composite numbers whose multiplicative digital root is 6. 3
6, 16, 28, 32, 44, 48, 68, 74, 82, 84, 86, 116, 123, 128, 132, 144, 147, 148, 161, 168, 174, 182, 184, 186, 213, 218, 224, 228, 231, 238, 242, 244, 246, 264, 267, 272, 276, 282, 288, 289, 298, 312, 321, 328, 344, 368, 374, 377, 378, 382, 386, 387, 414, 417, 418, 422 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A201019 with respect to A034053.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

Number 128 is in sequence because 1*2*8=16, 1*6=6.

MATHEMATICA

mdr6Q[n_]:=CompositeQ[n]&&NestWhile[Times@@IntegerDigits[#]&, n, #>9&] ==6; Select[Range[500], mdr6Q] (* Harvey P. Dale, May 30 2015 *)

CROSSREFS

Cf. A201019 (primes whose multiplicative digital root is 6), A034053 (numbers whose multiplicative digital root is 6).

Sequence in context: A265389 A320693 A274848 * A088818 A032422 A164052

Adjacent sequences:  A201017 A201018 A201019 * A201021 A201022 A201023

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, Nov 25 2011

STATUS

approved

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Last modified August 22 02:44 EDT 2019. Contains 326169 sequences. (Running on oeis4.)