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A046516
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Numbers with multiplicative persistence value 7.
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5
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68889, 68898, 68988, 69888, 86889, 86898, 86988, 88689, 88698, 88869, 88896, 88968, 88986, 89688, 89868, 89886, 96888, 98688, 98868, 98886, 168889, 168898, 168988, 169888, 186889, 186898, 186988, 188689, 188698, 188869, 188896, 188968
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listen;
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OFFSET
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1,1
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COMMENTS
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The product of the digits of each term is 27648, 47628, 64827, 84672, 134217728, 914838624, 1792336896, 3699376128, 48814981614, 134481277728, 147483721728 or 1438916737499136 (sequence A350185).
The first 62 terms produce 27648.
The first term that produces 47628 is a(63).
The first term that produces 64827 is a(233).
The first term that produces 84672 is a(235).
The first term that produces 134217728 is a(1753110).
The first term that produces 914838624 is a(17835449).
The first term that produces 1792336896 is a(18235677).
The first term that produces 3699376128 is a(23853261).
The first term that produces 48814981614 is a(66441891).
The first term that produces 134481277728 is a(452601087).
The first term that produces 147483721728 is a(425636434).
The first term that produces 1438916737499136 is somewhere after a(500*10^6). (End)
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LINKS
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EXAMPLE
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68889 -> [ 27648 ][ 2688 ][ 768 ][ 336 ][ 54 ][ 20 ][ 0 ] -> one digit in seven steps.
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MAPLE
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mp:= proc(n) option remember;
if n <= 9 then return 0 fi;
1+procname(convert(convert(n, base, 10), `*`))
end proc:
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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