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A239869 Numbers n such that n divides A239868(n). 1
1, 6, 7, 9, 14, 21, 37, 69, 670, 3471, 3477, 5160, 9500, 15432, 67054, 302224, 791733, 861781, 1425779, 6242689, 71511220, 187308565, 318733908, 336841318, 343858368, 499742949, 4088136488, 4172097579, 9981207398 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A239868 = partial sums of A054024, where A054024(n) = sigma(n) mod n.

Values of n for which A239868(n) / n is integer.

a(30) > 3*10^11. - Giovanni Resta, Mar 29 2014

LINKS

Table of n, a(n) for n=1..29.

EXAMPLE

a(4) = 9 is in the sequence because A239868(9) / 9 = 18 / 9 = 2 is integer.

PROG

(MAGMA) [n: n in [1..10000] | u eq 0 where u is ((&+[SumOfDivisors (k) mod k: k in [1..n]]) mod n)]

CROSSREFS

Cf. A000203, A054024, A239868.

Sequence in context: A168614 A045014 A047591 * A289547 A329912 A187922

Adjacent sequences:  A239866 A239867 A239868 * A239870 A239871 A239872

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Mar 28 2014

EXTENSIONS

a(16)-a(29) from Giovanni Resta, Mar 29 2014

STATUS

approved

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Last modified February 20 12:34 EST 2020. Contains 332076 sequences. (Running on oeis4.)