cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A380900 Integers k such that k = Sum k/(p_i + j), where p_i are the prime factors of k (with multiplicity). Case j = -2.

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%I A380900 #9 Mar 02 2025 23:48:09
%S A380900 3,125,16807,29155,33275,50575,90475,7761061,8857805,11796113,
%T A380900 13463065,20462645,21102389,24084445,35496425,36606185,63500525,
%U A380900 65485805,73776725,99798725,113597825,117779585,178056445,193155305,200599525,203878325,204311525,251218345
%N A380900 Integers k such that k = Sum k/(p_i + j), where p_i are the prime factors of k (with multiplicity). Case j = -2.
%e A380900 29155 = 5*7^3*17 = 29155/(5-2) + 29155*3/(7-2) + 29155/(17-2)
%p A380900 with(numtheory): P:=proc(q,h) local k,n,v; v:=[];
%p A380900 for n from 1 by 2 to q do if n=add(n*k[2]/(k[1]+h),k=ifactors(n)[2]) then v:=[op(v),n]; fi;
%p A380900 od; op(v); end: P(251218345,-2);
%Y A380900 Cf. A380888, A380889, A380901, A380923-A380928.
%K A380900 nonn
%O A380900 1,1
%A A380900 _Paolo P. Lava_, Feb 09 2025