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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A243810 Odd squares which are the sum of the divisors of some n.

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%I A243810 #22 Sep 27 2014 16:11:57
%S A243810 1,121,961,116281,294849,423801,2989441,7958041,26904969,35676729,
%T A243810 51279921,71622369,361722361,962922961,1891467081,1902442689,
%U A243810 3255501249,4364319969,4755619521,5215583961,6431879601,6561486009,6835486329,7496615889,8666306649,9712693809
%N A243810 Odd squares which are the sum of the divisors of some n.
%C A243810 Odd terms of A038688, where most of the terms are even.
%C A243810 The corresponding values in A228061 are: 1, 11, 31, 341, 543, 651, 1729, 2821, ...
%C A243810 Among the known terms, the only prime powers are 121 and 961.
%C A243810 Next term is greater than 10^8.
%H A243810 Hiroaki Yamanouchi, <a href="/A243810/b243810.txt">Table of n, a(n) for n = 1..183</a>
%e A243810 121 being an odd square and satisfying sigma(81) = 121, 121 is in the sequence.
%t A243810 Select[DivisorSigma[1,Range[72000000]],OddQ[#]&&IntegerQ[Sqrt[#]]&] (* _Harvey P. Dale_, Aug 18 2014 *)
%Y A243810 Cf. A000203, A038688, A228061.
%K A243810 nonn
%O A243810 1,2
%A A243810 _Michel Marcus_, Jun 11 2014
%E A243810 a(13)-a(26) from _Hiroaki Yamanouchi_, Sep 27 2014