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A046464
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Numbers k such that the concatenation of numbers from 1 to k is the product of 5 primes (not necessarily distinct).
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2
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8, 17, 25, 41, 47, 55, 56, 63, 77, 94, 101, 103, 107
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[Range[100], PrimeOmega@FromDigits@Flatten@ IntegerDigits@ Range@# == 5 &] (* Robert Price, Oct 11 2019 *)
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CROSSREFS
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KEYWORD
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nonn,base,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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