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A380925 Integers k such that k = Sum k/(p_i + j), where p_i are the prime factors of k (with multiplicity). Case j = -4.

%I A380925 #4 Mar 03 2025 11:13:54
%S A380925 5,75,100,343,1125,1500,2000,5145,6860,16875,22500,30000,40000,77175,
%T A380925 102900,107653,137200,253125,337500,352947,450000,470596,600000,
%U A380925 800000,1157625,1543500,1614795,2058000,2153060,2744000,3796875,5062500,5294205,6750000,7058940
%N A380925 Integers k such that k = Sum k/(p_i + j), where p_i are the prime factors of k (with multiplicity). Case j = -4.
%e A380925 337500 = 2^2*3^3*5^5 = 337500*2/(2-4) + 337500*3/(3-4) + 337500*5/(5-4)
%p A380925 with(numtheory): P:=proc(q, h) local k, n, v; v:=[];
%p A380925 for n from 1 to q do if n=add(n*k[2]/(k[1]+h), k=ifactors(n)[2]) then v:=[op(v), n];
%p A380925 fi; od; op(v); end: P(7058940, -4);
%Y A380925 Cf. A380888, A380889, A380900, A380901, A380923, A380924, A380926 - A380928.
%K A380925 nonn,easy
%O A380925 1,1
%A A380925 _Paolo P. Lava_, Mar 03 2025