login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A121743 Values of the Ramanujan tau triplets mod 691 such that three consecutive Ramanujan tau numbers are congruent mod 691. 4
0, 276, 91, 79, 0, 0 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Corresponding indices of the Ramanujan tau triplets mod 691 are listed in A121742[n] = {290217,477155,1051085,1153412,1409635,1409636,...}. All a(n) belong to the Ramanujan tau twins mod 691 A121734[n]. There are also quadruplets in the Ramanujan tau mod 691 such that A046694[n] = A046694[n+1] = A046694[n+2] = A046694[n+3]. The first such Ramanujan tau Quadruplet mod 691 starts with A046694[1409635] = 0.

LINKS

Eric Weisstein Link to a section of The World of Mathematics. Ramanujan's Tau Function.

FORMULA

a(n) = A000594[A121742[n]] mod 691. a(n) = A046694[A121742[n]].

MATHEMATICA

Do[f=Mod[DivisorSigma[11, n], 691]; g=Mod[DivisorSigma[11, n+1], 691]; h=Mod[DivisorSigma[11, n+2], 691]; If[f==g&&g==h, Print[{n, f}]], {n, 1, 1500000}]

CROSSREFS

Cf. A121742, A121733, A121734, A046694, A000594.

Sequence in context: A130292 A133536 A075666 * A084802 A003903 A131884

Adjacent sequences:  A121740 A121741 A121742 * A121744 A121745 A121746

KEYWORD

nonn

AUTHOR

Alexander Adamchuk (alex(AT)kolmogorov.com), Aug 19 2006

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 16 02:51 EST 2012. Contains 205860 sequences.