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A292763
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Numbers m such that sigma(m)+phi(m) == 2 mod 4.
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3
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1, 3, 5, 6, 7, 10, 11, 13, 14, 17, 19, 20, 22, 23, 26, 27, 29, 31, 34, 37, 38, 40, 41, 43, 45, 46, 47, 52, 53, 54, 58, 59, 61, 62, 67, 68, 71, 73, 74, 79, 80, 82, 83, 86, 89, 90, 94, 97, 101, 103, 104, 106, 107, 109, 113, 116, 117, 118, 122, 127, 131, 134, 136, 137, 139, 142, 146, 148, 149, 151, 153, 157
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OFFSET
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1,2
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COMMENTS
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LINKS
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N. J. A. Sloane, Three (No, 8) Lovely Problems from the OEIS, Experimental Mathematics Seminar, Rutgers University, Oct 05 2017, Part I, Part 2, Slides. (Mentions this sequence)
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MATHEMATICA
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Do[If[Mod[DivisorSigma[1, n] + EulerPhi[n], 4]==2, Print[n]], {n, 1, 10^3}] (* Vincenzo Librandi, Oct 02 2017 *)
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PROG
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(PARI) isok(m) = ((sigma(m)+eulerphi(m)) % 4) == 2; \\ Michel Marcus, Oct 02 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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STATUS
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approved
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