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.

A088825 Numbers n such that the sum of largest prime factors of numbers from 1 to n is divisible by n.

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%I A088825 #14 Apr 27 2017 09:21:53
%S A088825 1,2,8,9,32,62,558,993,995,1947,2150,4343,9944,10977,43054658,
%T A088825 202275890,2291937393,2459073795,2836929091,3737529738,21382629569,
%U A088825 248208997602,389691028017,838566394212,1019000924619
%N A088825 Numbers n such that the sum of largest prime factors of numbers from 1 to n is divisible by n.
%C A088825 a(21) > 15*10^9. - _Donovan Johnson_, Nov 01 2009
%C A088825 a(22) > 10^11. - _Donovan Johnson_, Jul 09 2010
%C A088825 a(26) > 5*10^12. - _Giovanni Resta_, Apr 25 2017
%F A088825 Solutions to Mod[A088822[x], x]=0.
%t A088825 gp[n_] := If[n==1, 0, FactorInteger[n][[-1, 1]]]; Flatten@ Position[ Accumulate[ gp /@ Range[10^5]] / Range[10^5], _Integer] (* _Giovanni Resta_, Apr 25 2017 *)
%Y A088825 Cf. A088821-A088824.
%K A088825 nonn
%O A088825 1,2
%A A088825 _Labos Elemer_, Oct 22 2003
%E A088825 More terms from _Ray Chandler_, Oct 31 2003
%E A088825 a(17)-a(20) from _Donovan Johnson_, Nov 01 2009
%E A088825 a(21) from _Donovan Johnson_, Jul 09 2010
%E A088825 a(22)-a(25) from _Giovanni Resta_, Apr 25 2017