A199993 - OEIS

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A199993

Composite numbers whose multiplicative persistence is 3.

39, 49, 55, 57, 66, 68, 69, 74, 75, 78, 86, 87, 88, 93, 94, 95, 96, 98, 147, 155, 159, 166, 168, 169, 174, 175, 178, 186, 187, 188, 189, 194, 195, 196, 198, 236, 238, 246, 247, 248, 249, 264, 266, 267, 272, 274, 276, 279, 284, 288, 289, 292, 294, 297, 298, 299

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Complement of A046503 with respect to A046512.

LINKS

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

Eric Weisstein's World of Mathematics, Multiplicative Persistence

FORMULA

{ A046512 } minus { A046503 }.

EXAMPLE

147 -> 1 * 4 * 7 -> [ 28 ] -> 2 * 8 -> [ 16 ] -> 1 * 6 -> [ 6 ] -> one digit in three steps.