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A191599 Numbers n such that n does not divide Ramanujan's tau(n). 2
11, 13, 17, 19, 22, 23, 26, 29, 31, 33, 34, 37, 38, 39, 41, 43, 44, 46, 47, 51, 52, 53, 55, 57, 58, 59, 61, 62, 65, 66, 67, 68, 69, 71, 73, 74, 76, 77, 78, 79, 82, 83, 85, 86, 87, 89, 93, 94, 95, 97, 99, 101, 102, 103, 104, 106, 107, 109, 110, 111, 113, 114 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The sequence has his first 45 terms in common with A068191.

The sequence is a subsequence of A068191.

Complement of A063938. - Omar E. Pol, Aug 28 2011

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

B. Ramakrishnan and Brundaban Sahu, Rankin-Cohen brackets and Van der Pol-type identities for the Ramanujan's tau function, arXiv:0711.3512 [math.NT], 2007, pp. 14. See Corollary 2.11

EXAMPLE

For n=1, a(1)=11 since 11 does not divide tau(11) = 534612.

MAPLE

with(numtheory): tn := proc(n) modp(-840*sum(k^4*sigma(k)*sigma(n-k), k=1..n-1), n); end; ser := proc(a, b) local n, lis; lis := []; for n from a to b do if tn(n) <> 0 then lis := [op(lis), n]; fi; od; lis; end;

MATHEMATICA

Select[Range[120], !Divisible[RamanujanTau[#], #]&] (* Jean-Fran├žois Alcover, Nov 29 2017 *)

CROSSREFS

Cf. A000594, A068191.

Sequence in context: A061116 A048388 A068191 * A084374 A063193 A056758

Adjacent sequences:  A191596 A191597 A191598 * A191600 A191601 A191602

KEYWORD

nonn

AUTHOR

Luis H. Gallardo, Jun 08 2011

STATUS

approved

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Last modified July 23 03:00 EDT 2019. Contains 325230 sequences. (Running on oeis4.)