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%I #15 Aug 26 2020 20:44:46
%S 1,9,25,225,289,729,1681,2401,2601,3481,5041,6561,7225,7921,10201,
%T 15129,15625,17161,18225,19881,21609,27889,28561,29929,31329,35721,
%U 42025,45369,59049,60025,62001,65025,71289,83521,85849,87025,88209,91809,114921,123201,126025,130321,140625,146689,154449,164025,172225
%N Odd numbers k such that A064989(sigma(k)) >= k.
%C Applying A064989 to these terms and sorting into ascending order gives A326182.
%C Conversely, this sequence is obtained when the sequence b(n) = A003961(A326182(n)) is sorted into ascending order.
%C Not all terms are squares. For example, 12121028325 = A003961(A326183(1)) = 3^6 * 5^2 * 7^4 * 277 is also term, and this is true for all terms of A326183 similarly prime shifted. Interestingly, for n = 1..24, A003961(A326183(n)) is a term of A228058.
%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>
%o (PARI)
%o A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o isA337344(n) = ((n%2)&&(A064989(sigma(n))>=n));
%Y Odd terms of A337343.
%Y Cf. A000203, A003961, A064989, A228058, A326042, A326182, A326183.
%K nonn
%O 1,2
%A _Antti Karttunen_, Aug 26 2020
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