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A126164 Sum of the proper exponential divisors of n. 6
0, 0, 0, 2, 0, 0, 0, 2, 3, 0, 0, 6, 0, 0, 0, 6, 0, 6, 0, 10, 0, 0, 0, 6, 5, 0, 3, 14, 0, 0, 0, 2, 0, 0, 0, 36, 0, 0, 0, 10, 0, 0, 0, 22, 15, 0, 0, 18, 7, 10, 0, 26, 0, 6, 0, 14, 0, 0, 0, 30, 0, 0, 21, 14, 0, 0, 0, 34, 0, 0, 0, 48, 0, 0, 15 (list; graph; refs; listen; history; internal format)
OFFSET

1,4

COMMENTS

The e-divisors (or exponential divisors) of x=Product p(i)^r(i) are all numbers of the form Product p(i)^s(i) where s(i) divides r(i) for all i.

LINKS

Ant King, Mathematica programs for A126164 - A126166

Eric Weisstein's World of Mathematics, e-Divisor.

FORMULA

a(n)=esigma(n)-n; a(n)=A051377-n

EXAMPLE

The exponential divisors of 240 are 30, 60 and 240, so a(240)=30+60=90

CROSSREFS

Cf. A051377, A049419, A054979, A054980.

Sequence in context: A054923 A057108 A063958 * A145007 A151670 A153587

Adjacent sequences:  A126161 A126162 A126163 * A126165 A126166 A126167

KEYWORD

easy,nonn

AUTHOR

Ant King (mathstutoring(AT)ntlworld.com), Dec 21 2006

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Last modified February 17 15:44 EST 2012. Contains 206050 sequences.