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A070600
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Largest number with n prime factors where all factors are less than or equal to n.
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0
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0, 4, 27, 81, 3125, 15625, 823543, 5764801, 40353607, 282475249, 285311670611, 3138428376721, 302875106592253, 3937376385699289, 51185893014090757, 665416609183179841, 827240261886336764177, 14063084452067724991009
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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a(2) = 4 (4=2*2 has 2 factors and 2 is the largest prime number <= 2).
a(3) = 27 (27=3*3*3 has 3 factors and 3 is the largest prime number <= 3).
a(4) = 81 (81=3*3*3*3 has 4 factors and 3 is the largest prime number <= 4).
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MATHEMATICA
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a[n_] := If[n == 1, 0, If[PrimeQ[n], n, NextPrime[n, -1]]^n];
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PROG
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(PARI) a(n) = if (n==1, 0, precprime(n)^n); \\ Michel Marcus, Sep 24 2020
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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Jostein Trondal (jallamekk(AT)hotmail.com), May 13 2002
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STATUS
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approved
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