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A121067
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a(n) = the n-th divisor of n^n (when the positive divisors of n^n are written in order from smallest to largest).
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4
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1, 2, 9, 8, 625, 8, 117649, 128, 6561, 32, 25937424601, 27, 23298085122481, 112, 375, 32768, 48661191875666868481, 72, 104127350297911241532841, 250, 2401, 1024, 907846434775996175406740561329, 162, 59604644775390625, 2704, 2541865828329
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OFFSET
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1,2
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COMMENTS
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This is also the n-th divisor of n^(n-1); any divisor with a factor of p^n is preceded by n smaller powers of p in the divisor list. [Franklin T. Adams-Watters, Sep 21 2009]
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LINKS
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FORMULA
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EXAMPLE
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1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 24, 27, 32, 36, 48, 54, 64,... is the beginning of the sequence of divisors of 6^6 = 46656. 8 is the 6th term of this sequence of divisors (which is sequence A114334), so a(6) = 8.
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MAPLE
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a:= n-> sort([numtheory[divisors](n^(n-1))[]])[n]:
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MATHEMATICA
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PROG
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(PARI) m=27; for(n=1, m, d=divisors(n^n); print1(d[n], ", ")) \\ Klaus Brockhaus, Aug 14 2006
(GAP) List([1..30], n->DivisorsInt(n^n)[n]); # Muniru A Asiru, Mar 06 2019
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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