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Smallest number m such that number of times m divides k! is almost k/n for large k, i.e., smallest m with A090624(m)=n.
1

%I #6 Jul 29 2017 04:11:46

%S 1,2,3,8,5,32,7,128,25,512,11,2048,13,8192,2187,32768,17,131072,19,

%T 524288,121,2097152,23,8388608,169,33554432,1594323,134217728,29,

%U 536870912,31,2147483648,289,8589934592,129140163,34359738368,37

%N Smallest number m such that number of times m divides k! is almost k/n for large k, i.e., smallest m with A090624(m)=n.

%F a(n) = min_p{p prime and n divisible by p-1} p^(n/(p-1)).

%F a(p-1) = p.

%F a(2n+1) = 2^(2n+1).

%F Smallest divisor of A091137(n) which is not a divisor of A091137(n-1).

%e a(2)=3 noting that 100! is a multiple of 3^48 and 48 is almost 100/2.

%Y Cf. A090622, A090624, A091137.

%K nonn

%O 0,2

%A _Henry Bottomley_, Dec 19 2003