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Search: id:A063940
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| A063940 |
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Composite n such that Ramanujan's function tau(n) (A000594) is not divisible by n. |
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+0
2
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| 22, 26, 33, 34, 38, 39, 44, 46, 51, 52, 55, 57, 58, 62, 65, 66, 68, 69, 74, 76, 77, 78, 82, 85, 86, 87, 93, 94, 95, 99, 102, 104, 106, 110, 111, 114, 116, 117, 118, 119, 121, 122, 123, 124, 129, 130, 132, 133, 134, 136, 138, 141, 142, 143, 145, 146, 148, 152, 153
(list; graph; listen)
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OFFSET
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1,1
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EXAMPLE
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Tau(22) = 18643272 which Mod( Tau(22), 22) == 10.
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MATHEMATICA
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Select[ Range[ 70 ], Mod[ CoefficientList[ Take[ Expand[ Product[ (1 - x^k)^24, {k, 1, 70} ] ], 70 ], x ][ [ # ] ], # ] != 0 && ! PrimeQ[ # ] & ]
(* First do *) <<NumberTheory`Ramanujan` (* then *) Select[ Range[ 153], Mod[ RamanujanTau[ # ], # ] != 0 && ! PrimeQ[ # ] &] (from Dean Hickerson (dean(AT)math.ucdavis.edu), Jan 03 2003)
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CROSSREFS
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Cf. A063938, A007659.
Sequence in context: A124177 A066059 A084891 this_sequence A046442 A101549 A038355
Adjacent sequences: A063937 A063938 A063939 this_sequence A063941 A063942 A063943
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KEYWORD
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nonn
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AUTHOR
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Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 31 2001
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