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 A194948 Numbers n such that sum of aliquot divisors of n, sigma(n) - n, is a cube. 3
 1, 2, 3, 5, 7, 10, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 49, 53, 56, 59, 61, 67, 69, 71, 73, 76, 79, 83, 89, 97, 101, 103, 107, 109, 113, 122, 127, 131, 133, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For prime numbers, the sum of their aliquot divisors is exactly 1 = 1^3. LINKS Harvey P. Dale, Table of n, a(n) for n = 1..2500 EXAMPLE a(6) = 10, since the sum of aliquot divisors 1 + 2 + 5 = 8 = 2^3. MAPLE for n do s:=numtheory[sigma](n)-n; if root(s, 3)=trunc(root(s, 3)) then print(n); fi; od: MATHEMATICA Select[Range[250], IntegerQ[Power[DivisorSigma[1, #]-#, (3)^-1]]&] (* Harvey P. Dale, Nov 25 2011 *) CROSSREFS Cf. A020477, A073040. Sequence in context: A235050 A117286 A169802 * A266679 A285257 A191211 Adjacent sequences:  A194945 A194946 A194947 * A194949 A194950 A194951 KEYWORD nonn AUTHOR Martin Renner, Oct 13 2011 STATUS approved

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