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A063940 Composite numbers k such that Ramanujan's function tau(k) (A000594) is not divisible by k. 1
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; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..59.

EXAMPLE

22 is a term because Ramanujan's tau(22) = 18643272 and 18643272 mod 22 = 10.

MATHEMATICA

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[ # ] &] (* Dean Hickerson, Jan 03 2003 *)

CROSSREFS

Cf. A063938, A007659.

Sequence in context: A066059 A084891 A162422 * A046442 A101549 A277624

Adjacent sequences:  A063937 A063938 A063939 * A063941 A063942 A063943

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Aug 31 2001

STATUS

approved

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Last modified November 13 17:34 EST 2019. Contains 329106 sequences. (Running on oeis4.)