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.

A382469 Numbers k such that the largest prime factor of k equals the sum of its remaining distinct prime factors.

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%I A382469 #19 May 31 2025 19:26:42
%S A382469 30,60,70,90,120,140,150,180,240,270,280,286,300,350,360,450,480,490,
%T A382469 540,560,572,600,646,700,720,750,810,900,960,980,1080,1120,1144,1200,
%U A382469 1292,1350,1400,1440,1500,1620,1750,1798,1800,1920,1960,2160,2240,2250,2288,2400,2430,2450,2584,2700,2800,2880,3000,3135,3146,3240
%N A382469 Numbers k such that the largest prime factor of k equals the sum of its remaining distinct prime factors.
%C A382469 A larger than usual number of terms is provided in order to distinguish this sequence from A365795, from which it first differs at n = 58 (a(58) = 3135 is missing from A365795).
%C A382469 First differs from A071140 at n = 140.
%H A382469 Paolo Xausa, <a href="/A382469/b382469.txt">Table of n, a(n) for n = 1..10000</a>
%t A382469 A382469Q[k_] := Last[#] == Total[Most[#]] & [FactorInteger[k][[All, 1]]];
%t A382469 Select[Range[4000], A382469Q]
%Y A382469 Positions of zeros in A382468.
%Y A382469 Supersequence of A365795.
%Y A382469 Cf. A006530, A027748, A071140, A221054.
%K A382469 nonn
%O A382469 1,1
%A A382469 _Paolo Xausa_, Mar 31 2025