login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS").
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A127814 a(n) = numerator of b(n), where b(1) = 2, b(n) = b(n-1) - 1/b(n-1). 4
2, 3, 5, -11, 779, 497941, 181860254581, 16687694789137362648661, -263439569256003706800705587722279993788907979, 81512663708476146329709015825571064954724426915346799560162522434680208602364731247764459 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Every term of this sequence of numerators is coprime to every other term.

LINKS

Table of n, a(n) for n=1..10.

Clark Kimberling, Polynomials associated with reciprocation, JIS 12 (2009) 09.3.4

EXAMPLE

The b() sequence is 2, 3/2, 5/6, -11/30, 779/330, 497941/257070, 181860254581/128005692870, ...

MATHEMATICA

f[l_List] := Append[l, l[[ -1]] - 1/l[[ -1]]]; Numerator[Nest[f, {2}, 10]] (* Ray Chandler, Feb 07 2007 *)

Numerator/@NestList[#-1/#&, 2, 10]  (* Harvey P. Dale, Apr 30 2011 *)

CROSSREFS

Cf. A127815.

Sequence in context: A327428 A220346 A242995 * A162253 A321855 A112978

Adjacent sequences:  A127811 A127812 A127813 * A127815 A127816 A127817

KEYWORD

easy,frac,sign

AUTHOR

Leroy Quet, Jan 30 2007

EXTENSIONS

Extended by Ray Chandler, Feb 07 2007

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 30 15:45 EST 2020. Contains 338807 sequences. (Running on oeis4.)