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%I #6 Jun 17 2019 18:01:57
%S 97560000,140040000,161640000,188280000,392760000,414360000,429480000,
%T 432360000,443160000,474840000,494280000,522360000,582840000,
%U 589320000,673560000,715320000,767160000,842040000,888120000,903960000,918360000,932760000,1026360000,1047240000
%N Numbers n for which A003961(n) <= A064989(sigma(A003961(n))), but which are not squares.
%C At least for 1 <= n <= 24 it holds that A052126(a(n)) is square, and moreover, apart from a(20), that square is 360000, while A052126(a(20)) = A052126(903960000) = 29160000.
%C The largest prime factors (that are also unitary in case of 24 initial terms) are A006530(a(n)): 271, 389, 449, 523, 1091, 1151, 1193, 1201, 1231, 1319, 1373, 1451, 1619, 1637, 1871, 1987, 2131, 2339, 2467, 31, 2551, 2591, 2851, 2909.
%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%Y Setwise difference A326182 \ A000290.
%Y Cf. A000203, A003961, A006530, A052126, A064989.
%K nonn
%O 1,1
%A _Antti Karttunen_, Jun 17 2019
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