

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
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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



