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A045613
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Minimal elements of pairs of "Super Unitary Amicable Numbers", sorted by their minimal elements.
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4
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33, 105, 110, 208, 268, 455, 695, 812, 1609, 1808, 1892, 1913, 2096, 2145, 3123, 3272, 3867, 4129, 5424, 5600, 5916, 6524, 6783, 7069, 7119, 7875, 9716, 10506, 11088, 11265, 11552, 12324, 12892, 12939, 13712, 14210, 15429, 15762, 17252, 17490, 18368, 19616
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OFFSET
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1,1
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LINKS
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FORMULA
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usigma(usigma(a)) = usigma(usigma(b)) = a+b where a<b and usigma(n) = A034448(n) is the sum of the unitary divisors of n. This sequence gives the values of a; A045614 gives the values of b.
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MATHEMATICA
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usigma[n_] := If[n == 1, 1, Times @@ (1 + Power @@@ FactorInteger[n])]; u[n_] := usigma[usigma[n]] - n; s = {}; Do[m = u[n]; If[m > n && u[m] == n, AppendTo[s, n]], {n, 1, 10000}]; s (* Amiram Eldar, Feb 18 2019 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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