A201020 - OEIS

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A201020

Composite numbers whose multiplicative digital root is 6.

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