A058040 Numbers k such that if p_1,p_2,...,p_m, m>1, are the prime factors of k, then there is some b>0 such that k = Sum_{i=1..m} b^(p_i).

12, 36, 576, 16464

Offset

1,1

Comments

No others < 1000000.

No others <= 10^9. - Sean A. Irvine, Jul 19 2022

Links

Table of n, a(n) for n=1..4.

Example

12=2^2*3=2^2+2^3 (b=2);
36=2^2*3^2=3^2+3^3 (b=3);
576=2^6*3^2=8^2+8^3 (b=8);
16464=2^4*3*7^3=4^2+4^3+4^7 (b=4).

Crossrefs

Sequence in context: A216381 A085331 A225100 * A130164 A144973 A043358

Adjacent sequences: A058037 A058038 A058039 * A058041 A058042 A058043

Keyword

nonn

Author

Naohiro Nomoto, Nov 21 2000

Extensions

Offset corrected and title clarified by Sean A. Irvine, Jul 19 2022

Status

approved