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A015787
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Numbers n such that phi(n) + 8 | sigma(n + 8), where phi = A000010 and sigma = A000203.
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1
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2, 18, 22, 34, 46, 48, 58, 94, 106, 132, 150, 166, 178, 180, 187, 214, 274, 346, 358, 394, 448, 466, 488, 526, 550, 562, 616, 624, 634, 660, 664, 744, 756, 772, 778, 782, 790, 798, 884, 886, 898, 934, 1138, 1174, 1186, 1354, 1366, 1438, 1618
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OFFSET
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1,1
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COMMENTS
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The first odd terms are 187, 2407, 98587, 388315.
If p > 5 is in A228353 then 2*p is in the sequence. (End)
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LINKS
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MAPLE
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select(t -> numtheory:-sigma(t+8) mod (numtheory:-phi(t)+8)=0, [$1..2000]); # Robert Israel, Jul 23 2020
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PROG
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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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