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A064556 Ramanujan's tau function (or tau numbers (A000594)) for 10^n. 3
1, -115920, 37534859200, -30328412970240000, -482606811957501440000, -2983637890141033828147200000 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (-115920, 124097412800, -11592000000000000, -10000000000000000000000).
MATHEMATICA
Table[ RamanujanTau[10^n], {n, 0, 5}]
PROG
(Perl) use bigint; use ntheory ":all"; say "$_ ", ramanujan_tau(10 ** $_) for 0..19; # Dana Jacobsen, Sep 05 2015
(PARI) taup(p, e)={
if(e==1,
(65*sigma(p, 11)+691*sigma(p, 5)-691*252*sum(k=1, p-1, sigma(k, 5)*sigma(p-k, 5)))/756
,
my(t=taup(p, 1));
sum(j=0, e\2,
(-1)^j*binomial(e-j, e-2*j)*p^(11*j)*t^(e-2*j)
)
)
};
a(n)=taup(5, n)*taup(2, n) \\ Charles R Greathouse IV, Sep 06 2015
CROSSREFS
Sequence in context: A237382 A255080 A232577 * A346903 A346887 A346830
KEYWORD
sign
AUTHOR
Robert G. Wilson v, Jan 04 2003
STATUS
approved

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Last modified July 18 09:00 EDT 2024. Contains 374378 sequences. (Running on oeis4.)