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A357494
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Numbers k such that s(k) = 4*k, where s(k) is the sum of divisors of k that have a square factor (A162296).
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5
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902880, 1534680, 361674720, 767685600, 4530770640, 4941414720, 5405788800, 5517818880, 16993944000, 20429240832, 94820077440
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OFFSET
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1,1
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COMMENTS
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Analogous to 4-perfect numbers (A027687) with nonsquarefree divisors.
Equivalently, numbers k such that A325314(k) = -3*k.
There are no numbers k below 10^11 such that A162296(k) = m*k for integers m > 4.
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LINKS
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EXAMPLE
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902880 is a term since A162296(902880) = 3611520 = 4*902880.
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MATHEMATICA
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q[n_] := Module[{f = FactorInteger[n], p, e}, p = f[[;; , 1]]; e = f[[;; , 2]]; Times @@ ((p^(e + 1) - 1)/(p - 1)) - Times @@ (p + 1) == 4*n]; Select[Range[2, 2*10^6], q]
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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