login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A128294 a(n) = denominator of b(n): b(1)=1; b(n+1) = b(n) + [b(1);b(2),...,b(n)], where [...] is a continued fraction of rational terms. 2
1, 1, 2, 16, 664, 5794064, 33447906751722, 27996871943383371722767277584, 1411648567276084801412872562665108454742185708848843396424 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Next term a(10) has roughly 117 digits. - R. J. Mathar, Sep 24 2007

LINKS

Table of n, a(n) for n=1..9.

MAPLE

L2cfrac := proc(L) local a, i; a := op(-1, L) ; for i from 2 to nops(L) do a := op(-i, L)+1/a ; od: RETURN(a) ; end: A128294 := proc() local b, n, bnxt; b := [1] ; for n from 2 to 10 do bnxt := op(-1, b)+L2cfrac(b) ; b := [op(b), bnxt] ; od: [seq( denom(b[i]), i=1..nops(b))] ; end: A128294() ; # R. J. Mathar, Sep 24 2007

CROSSREFS

Cf. A128293.

Sequence in context: A277036 A289202 A279324 * A278087 A015188 A005118

Adjacent sequences:  A128291 A128292 A128293 * A128295 A128296 A128297

KEYWORD

frac,nonn

AUTHOR

Leroy Quet, Feb 25 2007

EXTENSIONS

Corrected and extended by R. J. Mathar, Sep 24 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 5 20:00 EDT 2022. Contains 357261 sequences. (Running on oeis4.)