A077636 Length of periodic part of continued fraction expansion of square root of A051451(n), i.e., sqrt(lcm(1..x)) where x is a prime power from A000961.

0, 1, 2, 2, 4, 2, 2, 2, 4, 8, 18, 14, 36, 38, 232, 268, 110, 280, 4348, 3244, 32684, 148184, 207616, 9988, 1946132, 2154482, 13319736, 8971624, 12345748, 69705504, 159413696, 1184191340, 1183672188, 23656693528, 28963250020, 701296434876, 754283490078

Offset

1,3

Links

Table of n, a(n) for n=1..37.

Formula

a(n) = A003285(A051451(n)). - Michel Marcus, Sep 30 2019

Example

For A051451(10) = 360360, the periodic part is {3,2,1,132,1,2,3,1200} with 8 terms, so a(10) = 8.

Mathematica

pp = Join[{1}, Select[Range[2, 50], Mod[ #, # - EulerPhi[ # ]] == 0 &]]; Table[ Length[ Last[ ContinuedFraction[ Sqrt[ Apply[ LCM, Table[i, {i, 1, pp[[n]]}]]]]]], {n, 1, 31}]

Crossrefs

Cf. A000961, A003285, A051451.

Sequence in context: A114233 A279047 A063086 * A215847 A360460 A057000

Adjacent sequences: A077633 A077634 A077635 * A077637 A077638 A077639

Keyword

nonn,more

Author

Labos Elemer, Nov 13 2002

Extensions

Edited and extended by Robert G. Wilson v, Nov 14 2002

a(31) from Ray Chandler, Jan 16 2009

a(32)-a(35) from Chai Wah Wu, Sep 26 2019

a(36) from Chai Wah Wu, Sep 29 2019

a(37) from Chai Wah Wu, Sep 26 2021

Status

approved