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A199996 Composite numbers whose multiplicative persistence is 6. 0
6788, 6878, 6887, 7688, 7868, 7886, 8678, 8687, 8768, 8786, 8876, 16788, 16878, 16887, 17688, 17868, 17886, 18678, 18687, 18768, 18786, 18867, 18876, 23788, 23878, 24678, 24687, 24768, 24786, 24867, 24876, 26478, 26487, 26748, 26784, 26847, 26874, 27388 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A046506 with respect to A046515.

LINKS

Table of n, a(n) for n=1..38.

EXAMPLE

6788 -> [ 2688 ][ 768 ][ 336 ][ 54 ][ 20 ][ 0 ] -> one digit in six steps.

MATHEMATICA

persistence[n_] := Module[{cnt = 0, k = n}, While[k > 9, cnt++; k = Times @@ IntegerDigits[k]]; cnt]; Select[Range[30000], ! PrimeQ[#] && persistence[#] == 6 &] (* T. D. Noe, Nov 23 2011 *)

CROSSREFS

Cf. A046506 (primes whose multiplicative persistence is 6).

Sequence in context: A250332 A121106 A046515 * A266847 A345592 A345850

Adjacent sequences:  A199993 A199994 A199995 * A199997 A199998 A199999

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, Nov 13 2011

STATUS

approved

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Last modified October 3 02:59 EDT 2022. Contains 357230 sequences. (Running on oeis4.)