A225792 Numbers n such that the sum of first n nontrivial prime powers (A025475 excluding 1) is divisible by n.

1, 2, 3, 9, 13, 54, 384, 596, 7289, 18136, 226871, 1577601, 5240465, 13389981, 130707763, 157598052, 617834651, 998713177, 4596574856

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: A233190 A269154 A358829 * 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