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%I #9 Mar 26 2019 20:14:32
%S 8,27,105,125,231,343,627,897,935,1331,1581,1729,2197,2465,2967,3525,
%T 4123,4301,4715,4913,5487,6859,7035,7685,7881,9717,10707,11339,12167,
%U 14993,16377,17353,17655,20213,20915,23779,24389,24765,25327,26331,26765,29341,29607
%N Numbers x that are equal to lpf(x)*gpf(x)*(lpf(x)+gpf(x))/2, where lpf(x) and gpf(x) are the least and the greatest prime factors of x: A020639 and A006530.
%C This is A307108 with terms such that lpf(x)=gpf(x), that is, with cubes of primes.
%Y Cf. A000040, A020639, A006530, A307108.
%Y Cf. A262723 is the subsequence with terms such that lpf(x)!=gpf(x), and (lpf(x)+gpf(x))/2 a prime.
%K nonn
%O 1,1
%A _Alex Ratushnyak_, Mar 25 2019
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