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A225792 Numbers n such that the sum of first n nontrivial prime powers (A025475 excluding 1) is divisible by n. 2
1, 2, 3, 9, 13, 54, 384, 596, 7289, 18136, 226871, 1577601, 5240465, 13389981, 130707763, 157598052, 617834651, 998713177, 4596574856 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(16) > 146306912. There are 146306912 nontrivial prime powers <= 2^63. - Donovan Johnson, May 16 2013

a(20) > 41.2*10^9. - Giovanni Resta, May 16 2013

LINKS

Table of n, a(n) for n=1..19.

EXAMPLE

The sum of first 9 nontrivial prime powers is 4 + 8 + 9 + 16 + 25 + 27 + 32 + 49 + 64 = 234. Because 234 is divisible by 9, the latter is in the sequence.

CROSSREFS

Cf. A025475, A225791.

Sequence in context: A101234 A233190 A269154 * A057293 A109662 A116222

Adjacent sequences:  A225789 A225790 A225791 * A225793 A225794 A225795

KEYWORD

nonn,more

AUTHOR

Alex Ratushnyak, May 16 2013

EXTENSIONS

a(12)-a(15) from Donovan Johnson, May 16 2013

a(16)-a(19) from Giovanni Resta, May 16 2013

STATUS

approved

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Last modified October 7 17:44 EDT 2022. Contains 357275 sequences. (Running on oeis4.)