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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.

A194948 Numbers k such that sum of aliquot divisors of k, sigma(k) - k, is a cube.

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%I A194948 #23 Feb 23 2020 04:49:27
%S A194948 1,2,3,5,7,10,11,13,17,19,23,29,31,37,41,43,47,49,53,56,59,61,67,69,
%T A194948 71,73,76,79,83,89,97,101,103,107,109,113,122,127,131,133,137,139,149,
%U A194948 151,157,163,167,173,179,181,191,193,197,199,211,223,227,229,233
%N A194948 Numbers k such that sum of aliquot divisors of k, sigma(k) - k, is a cube.
%C A194948 For prime numbers, the sum of their aliquot divisors is exactly 1 = 1^3.
%H A194948 Amiram Eldar, <a href="/A194948/b194948.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..2500 from Harvey P. Dale)
%e A194948 a(6) = 10, since the sum of aliquot divisors 1 + 2 + 5 = 8 = 2^3.
%p A194948 for n do s:=numtheory[sigma](n)-n; if root(s,3)=trunc(root(s,3)) then print(n); fi; od:
%t A194948 Select[Range[250],IntegerQ[Power[DivisorSigma[1,#]-#, (3)^-1]]&] (* _Harvey P. Dale_, Nov 25 2011 *)
%Y A194948 Union of A000040 and A048698.
%Y A194948 Cf. A020477, A073040.
%K A194948 nonn
%O A194948 1,2
%A A194948 _Martin Renner_, Oct 13 2011