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A157848 Corresponding values of arithmetic means of divisors of numbers from A007340. 0
1, 3, 28, 45, 84, 182, 270, 620, 546, 1240, 1330, 1638, 1260, 1365, 2660, 8128, 6200, 6200, 6944, 8190, 9310, 7560, 8190, 18600, 15120, 18620, 16380, 25935, 30240, 32760, 63700, 55860, 40950, 55800, 117800, 98208, 105664, 117800, 121030, 173600, 167400, 155610 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A007340 = numbers n such that the arithmetic mean of divisors of n is integer and equal to one of the divisors of this numbers.

LINKS

Table of n, a(n) for n=1..42.

FORMULA

a(n)=sigma(A007340(n))/tau(A007340(n))=A000203((A007340(n))/A000005(A007340(n)).

EXAMPLE

a(3) = 28, because 28 is arithmetic mean of divisors of A007340(3)=140 and also is divisor of 140.

PROG

[SumOfDivisors(n) / NumberOfDivisors(n): n in[A007340(n)] ]

CROSSREFS

Cf. A000203, A007340, A000005.

Sequence in context: A037102 A042169 A041785 * A225674 A253653 A267360

Adjacent sequences: A157845 A157846 A157847 * A157849 A157850 A157851

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Mar 07 2009, Mar 09 2009

EXTENSIONS

Corrected and extended by Jaroslav Krizek, Mar 29 2015

STATUS

approved

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Last modified March 28 23:19 EDT 2023. Contains 361596 sequences. (Running on oeis4.)