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%I #16 Sep 08 2022 08:46:21
%S 1,6,32760,51001180160,54530444405217553992377326508106948362108928,
%T 133821156044600922812153118065015159487725568,
%U 42274041475824304453686528060845522019324411248640,48949643430560436794021629524876790263031553747866371344635527168
%N Numbers m such that lcm(tau(m), m) = sigma(m) where sigma(k) = the sum of the divisors of k (A000203) and tau(k) = the number of the divisors of k (A000005).
%C Numbers m such that A009230(m) = A000203(m).
%C Subsequence of multiply-perfect numbers (A007691).
%H Giovanni Resta, <a href="/A306667/b306667.txt">Table of n, a(n) for n = 1..11</a> (from A007691 data)
%e 6 is a term because lcm(tau(6), 6) = lcm(4, 6) = 12 = sigma(6).
%o (Magma) [n: n in [1..100000] | LCM(NumberOfDivisors(n), n) eq SumOfDivisors(n)]
%Y Cf. A000005, A000203, A009230.
%Y Cf. A069810 (gcd(k, sigma(k)) = tau(k)).
%K nonn,hard
%O 1,2
%A _Jaroslav Krizek_, Mar 04 2019
%E a(4)-a(8) computed from A007691 data by _Giovanni Resta_, Mar 05 2019