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%I #8 Jun 17 2019 15:23:00
%S 1,4,9,36,64,169,256,576,625,676,729,1024,1369,1521,1600,2304,2500,
%T 2809,2916,3136,4096,4489,5184,5476,5625,6084,6561,6889,7396,7744,
%U 9216,9409,10816,11236,12321,14400,14641,16129,17956,19044,22500,23104,24964,25281,26244,26569,27556,27889,28224,28561,33856,36864,37636,40000,40401
%N Numbers for which A003961(n) <= A064989(sigma(A003961(n))).
%C Not all terms are squares: the first nonsquare occurs as a(1427) = 97560000 = 2^6 * 3^2 * 5^4 * 271, and among the first 4011 terms (those <= 2^30), there are 24 of them, see A326183.
%H Antti Karttunen, <a href="/A326182/b326182.txt">Table of n, a(n) for n = 1..4011; all terms up to 2^30</a>
%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 A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ From A003961
%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 isA326182(n) = { my(u=A003961(n)); (u <= A064989(sigma(u))); };
%Y Cf. A000203, A000290, A003961, A064989, A286385, A326042, A326183 (nonsquares present).
%K nonn
%O 1,2
%A _Antti Karttunen_, Jun 16 2019
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