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Numbers n that share a prime factor with A276086(n).
11

%I #6 Mar 10 2019 19:32:05

%S 3,9,10,15,20,21,25,27,33,35,39,40,42,45,49,50,51,55,56,57,63,69,70,

%T 75,77,80,81,84,85,87,91,93,98,99,100,105,110,111,112,115,117,119,123,

%U 126,129,130,133,135,140,141,145,147,153,154,159,160,161,165,168,170,171,175,177,182,183,189,190,195,196,200,201,203,205

%N Numbers n that share a prime factor with A276086(n).

%C Numbers n for which A324198(n) <> 1.

%H Antti Karttunen, <a href="/A324584/b324584.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

%H <a href="/index/Pri#primorial_numbers">Index entries for sequences related to primorial numbers</a>

%o (PARI)

%o A276086(n) = { my(i=0,m=1,pr=1,nextpr); while((n>0),i=i+1; nextpr = prime(i)*pr; if((n%nextpr),m*=(prime(i)^((n%nextpr)/pr));n-=(n%nextpr));pr=nextpr); m; };

%o A324198(n) = gcd(n,A276086(n));

%o for(n=1, oo, if(1!=A324198(n), print1(n, ", ")));

%Y Cf. A276086, A324198.

%Y Cf. A324583 (complement).

%K nonn

%O 1,1

%A _Antti Karttunen_, Mar 10 2019