Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #7 Sep 19 2019 21:13:40
%S 1,1,1,2,1,1,1,1,1,2,2,1,1,1,1,4,1,1,1,1,2,2,1,1,1,3,1,2,1,1,1,1,1,2,
%T 1,2,1,1,1,2,2,1,2,1,1,4,1,1,1,2,3,2,1,1,1,2,2,2,1,1,1,1,1,4,1,1,1,1,
%U 1,2,4,1,1,1,1,6,1,2,1,1,2,2,1,1,2,2,1,2,1,1,1,2,1,2,1,1,1,1,3,2,2,1,1,1,1,8
%N Number of common divisors of n and A276086(n), with a(0) = 1.
%H Antti Karttunen, <a href="/A327168/b327168.txt">Table of n, a(n) for n = 0..16383</a>
%H Antti Karttunen, <a href="/A327168/a327168.txt">Data supplement: n, a(n) computed for n = 0..65537</a>
%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%F a(n) = A000005(A324198(n)).
%F a(n) = 1+A001222(A327167(n)) for n >= 1.
%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 A327168(n) = numdiv(gcd(n,A276086(n)));
%Y Cf. A000005, A001222, A276086, A324198, A327167.
%Y Cf. also A323878.
%K nonn
%O 0,4
%A _Antti Karttunen_, Sep 19 2019