OFFSET
1,3
FORMULA
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
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