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A133202
Number of divisors of the absolute value of Ramanujan tau numbers.
0
1, 8, 18, 14, 32, 48, 32, 80, 20, 120, 48, 108, 16, 112, 192, 26, 48, 96, 144, 192, 216, 144, 32, 384, 12, 80, 224, 120, 32, 420, 72, 192, 320, 160, 360, 210, 8, 576, 144, 792, 32, 432, 12, 216, 288, 84, 40, 180, 12, 96, 240, 128, 32, 448, 576, 832, 960, 120
OFFSET
1,2
LINKS
Bruce C. Berndt and Ken Ono, Ramanujan's unpublished manuscript on the partition and tau functions with proofs and commentary. Séminaire Lotharingien de Combinatoire, B42c (1999), pp. 63.
FORMULA
a(n) = number of divisors of abs. value of Ramanujan tau numbers.
MATHEMATICA
Table[DivisorSigma[0, RamanujanTau[n]], {n, 100}] (* T. D. Noe, Aug 22 2011 *)
PROG
(Perl) use ntheory ":all"; say scalar(divisors(abs(ramanujan_tau($_)))) for 1..100; # Dana Jacobsen, Sep 05 2015
(PARI) a(n)=numdiv(abs(ramanujantau(n))) \\ Charles R Greathouse IV, Feb 08 2017
CROSSREFS
Cf. A000594.
Sequence in context: A163900 A137788 A333828 * A217424 A332969 A322031
KEYWORD
nonn
AUTHOR
Ctibor O. Zizka, Dec 18 2007
EXTENSIONS
Corrected and extended by Carl Najafi, Aug 21 2011
STATUS
approved