login
A sixth of the smallest integer for which the number of divisors is the n-th composite.
0

%I #14 Sep 12 2022 03:22:04

%S 1,2,4,6,8,10,32,24,20,30,40,96,512,60,216,2048,150,160,120,140,1536,

%T 32768,864,210,131072,6144,280,480,2560,600,2097152,420,7776,1080,

%U 98304,10240,1050,13824,1120,393216,134217728,840,536870912,2400,1260,55296,7680,163840,6291456

%N A sixth of the smallest integer for which the number of divisors is the n-th composite.

%F a(n) = A005179(A002808(n))/6.

%e The first composite is A002808(1)=4. The smallest integer with 4 divisors is A005179(4) = 6, which divided by 6 yields a(1)=1.

%Y Cf. A002808, A005179, A061286, A187678.

%K nonn,less

%O 1,2

%A _Juri-Stepan Gerasimov_, Mar 12 2011