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 A324651 Bisection of A324650: a(n) = A000010(A276086(2*n)). 3

%I

%S 1,2,6,4,8,24,20,40,120,100,200,600,500,1000,3000,6,12,36,24,48,144,

%T 120,240,720,600,1200,3600,3000,6000,18000,42,84,252,168,336,1008,840,

%U 1680,5040,4200,8400,25200,21000,42000,126000,294,588,1764,1176,2352,7056,5880,11760,35280,29400,58800,176400,147000,294000,882000,2058

%N Bisection of A324650: a(n) = A000010(A276086(2*n)).

%H Antti Karttunen, <a href="/A324651/b324651.txt">Table of n, a(n) for n = 0..15015</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>

%F a(n) = A324650(2*n) = A000010(A276086(2*n)).

%o (PARI)

%o A324650(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)-1)*(prime(i)^(((n%nextpr)/pr)-1)); n-=(n%nextpr));pr=nextpr); (m); };

%o A324651(n) = A324650(n+n);

%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 A324651(n) = eulerphi(A276086(n+n));

%Y Cf. A000010, A276086, A324650.

%K nonn

%O 0,2

%A _Antti Karttunen_, Mar 10 2019

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Last modified August 4 01:37 EDT 2021. Contains 346441 sequences. (Running on oeis4.)