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%I #10 Aug 29 2020 06:51:55
%S 1,5,7,9,11,13,17,19,21,22,23,25,26,27,29,31,33,34,35,37,38,39,41,43,
%T 44,45,46,47,49,50,51,52,53,55,57,58,59,61,62,63,64,65,66,67,68,69,70,
%U 71,73,74,75,76,77,78,79,81
%N Numbers k such that k >= d(k)^2, where d(k) is the number of divisors of k.
%H Harvey P. Dale, <a href="/A035034/b035034.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = n + 52 for n >= 1209. - _Amiram Eldar_, Aug 29 2020
%t Select[Range[100],#>=DivisorSigma[0,#]^2&] (* _Harvey P. Dale_, May 05 2017 *)
%Y Complement of A034884.
%Y Cf. A000005, A035033, A035035.
%K nonn
%O 1,2
%A _N. J. A. Sloane_.