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a(n) is the largest number j whose n-th power has exactly j divisors.
5

%I #6 Jan 27 2019 08:47:38

%S 1,2,3,40,45,1,7,225,153,640,4851,6348,325,19474560,1,976,18513,1225,

%T 19,107747640000,81,1,23,245790720,49,2601,2133,3025,94221,

%U 56241820800,31,20063232,4225,15262600,4761,19236456,37,25462407801600,5929,2952832000,21921921

%N a(n) is the largest number j whose n-th power has exactly j divisors.

%C a(n) is the largest (and last) of the A323731(n) numbers in row n of A323730.

%C If a(n)=1 then n is a term in A323732; otherwise, n is a term in A323733.

%H Jon E. Schoenfield, <a href="/A323734/b323734.txt">Table of n, a(n) for n = 0..100</a>

%e The numbers j whose 3rd powers have exactly j divisors are 1, 28, and 40; the largest of these is 40, so a(3) = 40.

%e The only number j whose 5th power has exactly j divisors is 1, so a(1) = 1.

%Y Cf. A000005, A073049, A323730, A323731, A323732, A323733.

%K nonn

%O 0,2

%A _Jon E. Schoenfield_, Jan 26 2019