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.

A085718 Numbers n such that sopfr(n)/spf(n) is a semiprime and sopfr(n)/lpf(n) is a semiprime, where sopfr(n) = A001414(n) is sum of primes dividing n (with repetition), spf(n) and lpf(n) are smallest and largest primes dividing n, respectively. Also, spf(n)!=lpf(n).

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%I A085718 #6 Dec 15 2017 17:36:27
%S A085718 72,576,648,750,800,900,960,1080,3430,4116,4900,5880,6272,7000,7056,
%T A085718 7938,8400,8960,9450,10080,10752,11340,12096,13608,18750,20000,22500,
%U A085718 24000,25600,27000,28800,30375,30720,32400,34560,36450,36864,37268
%N A085718 Numbers n such that sopfr(n)/spf(n) is a semiprime and sopfr(n)/lpf(n) is a semiprime, where sopfr(n) = A001414(n) is sum of primes dividing n (with repetition), spf(n) and lpf(n) are smallest and largest primes dividing n, respectively. Also, spf(n)!=lpf(n).
%e A085718 648=2^3*3^4 is a term because 2+2+2+3+3+3+3 = 18 and 18/2 = 9 and 18/3 = 6.
%K A085718 nonn
%O A085718 1,1
%A A085718 _Jason Earls_, Jul 19 2003