Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #5 Mar 31 2019 00:17:01
%S 1,1,1,3,1,5,1,5,7,7,1,125,1,11,16807,75,1,245,1,343,161051,13,1,175,
%T 102487,17,11,1331,1,26411,1,7,371293,19,3293331899,300125,1,23,
%U 1419857,11,1,13,1,2197,161051,29,1,343,82055753,73525096183,2476099,4913,1,605,634933,19487171,6436343,31,1,65219,1,37,265837,147
%N Largest proper divisor of A324886(n).
%H Antti Karttunen, <a href="/A324896/b324896.txt">Table of n, a(n) for n = 1..2310</a>
%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</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) = A032742(A324886(n)) = A324895(A108951(n)).
%o (PARI)
%o A034386(n) = prod(i=1, primepi(n), prime(i));
%o A032742(n) = if(1==n,n,n/vecmin(factor(n)[,1]));
%o A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) }; \\ From A108951
%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 A324886(n) = A276086(A108951(n));
%o A324896(n) = A032742(A324886(n));
%Y Cf. A032742, A108951, A276086, A324886, A324895.
%K nonn
%O 1,4
%A _Antti Karttunen_, Mar 30 2019