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%I #11 Oct 22 2021 15:00:37
%S 18,4,1,3,11264,64000,82944,27599616
%N Least positive integer with exactly n representations as k/d(k), where d(k) = number of divisors of k.
%C 27599616 is the only number < 4*10^7 with exactly 7 representations as k/d(k). - _Donovan Johnson_, Sep 29 2012
%e Contribution from _Donovan Johnson_, Sep 29 2012: (Start)
%e a(1) = A051278(1) = 4. k/d(k) = 4 for exactly 1 k value: 36.
%e a(2) = A051279(1) = 1. k/d(k) = 1 for exactly 2 k values: 1 and 2.
%e a(3) = A051280(1) = 3. k/d(k) = 3 for exactly 3 k values: 9, 18 and 24.
%e a(4) = A217125(1) = 11264. k/d(k) = 11264 for exactly 4 k values: 360448, 585728, 630784 and 1115136.
%e a(5) = A217126(1) = 64000. k/d(k) = 64000 for exactly 5 k values: 4096000, 6656000, 7040000, 7168000 and 11520000.
%e a(6) = A217127(1) = 82944. k/d(k) = 82944 for exactly 6 k values: 7962624, 12939264, 13271040, 13934592, 21565440 and 23224320.
%e a(7) = 27599616. k/d(k) = 27599616 for exactly 7 k values: 10598252544, 17222160384, 17663754240, 18215746560, 18546941952, 28703600640 and 30911569920. (End)
%Y Cf. A051278, A051279, A051280, A217125, A217126, A217127.
%K nonn,hard
%O 0,1
%A _David W. Wilson_
%E a(4)-a(6) verified and a(7) added by _Donovan Johnson_, Sep 29 2012
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