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%I #15 Jun 10 2022 17:14:41
%S 1,1,2,4,8,96,384,2304,4608,18432,552960,19906560,796262400,
%T 33443020800,66886041600,267544166400,535088332800,32105299968000,
%U 2118949797888000,148326485852160000,10679506981355520000
%N a(n) is the quotient obtained when the totient of primorial (that is, the product of p-1 values) is divided by the LCM of the same p-1 values.
%H Muniru A Asiru, <a href="/A058262/b058262.txt">Table of n, a(n) for n = 0..150</a>
%e n=7: lcm(2-1, 3-1, 5-1, 7-1, 11-1, 13-1, 17-1) = lcm(1,2,4,6,10,12,16) = 240; phi(2*3*5*7*11*13*17) = phi(510510) = 92160 = A005867(8); a(7) = 92160/240 = 384.
%p with(numtheory):
%p nmax:=22: p:=seq([seq(ithprime(k)-1,k = 1 .. n)],n=1..nmax):
%p a:seq(phi(mul(ithprime(i),i=1..n))/lcm(seq(p[n][i],i=1..nops(p[n]))),n=1..nmax); # _Muniru A Asiru_, Jul 08 2018
%o (PARI) a(n) = my(v=vector(n+1, k, prime(k)-1)); prod(k=1, #v, v[k])/lcm(v); \\ _Michel Marcus_, Jul 08 2018
%Y Cf. A000010, A002110, A005867, A003418.
%K nonn
%O 0,3
%A _Labos Elemer_, Dec 06 2000
%E Definition revised by Editors, Jul 15 2018
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