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A175875
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Numbers n such that sigma(n+3) = 3*sigma(n).
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3
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3, 30237, 292317, 3116957, 4044037, 6902277, 73442597, 115767957, 137410557, 416776357, 526908197, 541579497, 695350653, 758403357, 1105731897, 1178082357, 1233277917, 1309742557, 1866261597, 1998267037, 2161411557, 2563416237, 2750761437, 2873771997, 2892203997, 3331848517, 3621735037, 3758847117
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OFFSET
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1,1
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COMMENTS
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LINKS
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PROG
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(PARI) isok(n) = sigma(n+3) == 3*sigma(n); \\ Michel Marcus, Oct 19 2013
(Magma) [n: n in [1..10^8] | SumOfDivisors(n+3) eq 3*SumOfDivisors(n)]; // Vincenzo Librandi, Jul 28 2017
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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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