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A165797 a(n) = n^( sigma(n) - tau(n) ). 0
1, 2, 9, 256, 625, 1679616, 117649, 8589934592, 3486784401, 100000000000000, 25937424601, 552061438912436417593344, 23298085122481, 83668255425284801560576, 332525673007965087890625 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

The power of n with exponent given by the difference between its sum of divisors and its count of divisors.

FORMULA

a(n) = n^(A000203(n)-A000005(n)) = n^A000203(n) / n^A000005(n) = n^A065608(n) .

EXAMPLE

a(4) = 4^(sigma(4)-tau(4)) = 4^(7-3) = 4^4 = 256.

CROSSREFS

Sequence in context: A114563 A112311 A067564 * A011823 A122894 A042675

Adjacent sequences:  A165794 A165795 A165796 * A165798 A165799 A165800

KEYWORD

nonn

AUTHOR

Jaroslav Krizek (jaroslav.krizek(AT)atlas.cz), Sep 27 2009

EXTENSIONS

Slightly edited by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 29 2009

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Last modified February 16 21:45 EST 2012. Contains 205978 sequences.