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A088824 Numbers n such that the sum of smallest prime factors of numbers from 1 to n is divisible by n. 5

%I

%S 1,2,7,14,78,113,153,439,462,1215,2294,8363,11102,12302,36382,38370,

%T 60398,199953,224090,421399,427131,1947938,2467022,2571633,62395623,

%U 462027217,2140648015,6418011931,43074345625,52714450814,71229445182,90719472005,105685014433

%N Numbers n such that the sum of smallest prime factors of numbers from 1 to n is divisible by n.

%H Giovanni Resta, <a href="/A088824/b088824.txt">Table of n, a(n) for n = 1..38</a> (terms < 7.5*10^12)

%F Solutions to Mod[A088821[x], x]=0.

%t smp[n_] := If[n==1, 0, FactorInteger[n][[1, 1]]]; s = Accumulate @ Array[ smp, 10^5]; Select[Range[10^5], Mod[s[[#]], #] == 0 &] (* _Giovanni Resta_, Apr 27 2017 *)

%Y Cf. A088821-A088825.

%K nonn

%O 1,2

%A _Labos Elemer_, Oct 22 2003

%E More terms from _Ray Chandler_, Oct 31 2003

%E a(27)-a(31) from _Donovan Johnson_, Jul 09 2010

%E a(32)-a(33) from _Giovanni Resta_, Apr 27 2017

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Last modified May 13 19:36 EDT 2021. Contains 343868 sequences. (Running on oeis4.)