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A332315
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Numbers k such that k and k + 1 have the same norm of the sum of divisors in Gaussian integers.
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1
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30514, 36777, 43978, 3474262, 5745125, 10628554, 16567494, 40831527, 58008301, 111798477, 142981839, 288834504, 392413941, 580867202, 650141557, 944224497, 967593411, 1874210882, 6306287377, 6442064745, 7377567197, 8121464245
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OFFSET
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1,1
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COMMENTS
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The first term, 30514, is also a number k such that k and k + 1 have the sum divisors in Gaussian integers: -54720 + 48960*i (where i is the imaginary unit). What is the next term with this property?
No more terms below 1.5*10^10.
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LINKS
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EXAMPLE
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MATHEMATICA
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csigma[n_] :=(Abs @ DivisorSigma[1, n, GaussianIntegers -> True])^2; seq = {}; n1 = csigma[1]; Do[n2 = csigma[n]; If[n1 == n2, AppendTo[seq, n - 1]]; n1 = n2, {n, 2, 5*10^5}]; seq
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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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