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A360524
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Numbers k such that A360522(k) = 2*k.
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1
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6, 12, 198, 240, 264, 270, 396, 540, 6720, 7920, 11880, 13770, 27540, 221760, 337440, 605880, 2500344, 6072570, 11135520, 12145140, 267193080, 441692160, 1112629770, 2225259540, 14575841280, 48955709880
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OFFSET
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1,1
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COMMENTS
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a(27) > 10^11, if it exists.
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LINKS
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EXAMPLE
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6 is a term since A360522(6) = 12 = 2 * 6.
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MATHEMATICA
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f[p_, e_] := p^e + e; q[n_] := Times @@ f @@@ FactorInteger[n] == 2*n; Select[Range[10^6], q]
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PROG
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(PARI) is(n) = {my(f = factor(n)); prod(i = 1, #f~, f[i, 1]^f[i, 2] + f[i, 2]) == 2*n; }
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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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