%I #6 Jul 20 2022 01:36:07

%S 12,36,576,16464

%N 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).

%C No others < 1000000.

%C No others <= 10^9. - _Sean A. Irvine_, Jul 19 2022

%e 12=2^2*3=2^2+2^3 (b=2);

%e 36=2^2*3^2=3^2+3^3 (b=3);

%e 576=2^6*3^2=8^2+8^3 (b=8);

%e 16464=2^4*3*7^3=4^2+4^3+4^7 (b=4).

%K nonn

%O 1,1

%A _Naohiro Nomoto_, Nov 21 2000

%E Offset corrected and title clarified by _Sean A. Irvine_, Jul 19 2022