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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A225843 Integral parts of sums of the reciprocals of the Collatz (3x+1) sequence starting with n. 3
1, 1, 2, 1, 2, 2, 2, 1, 3, 2, 2, 2, 2, 2, 2, 1, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 1, 3, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

a(n) = floor(sum(1/A070165(n,k): k = 1..A006577(n)));

conjecture: a(n) <= 3;

a(n) = 1 iff n = 2^k: a(A000079(n)) = 1, a(A057716(n)) > 1.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Index entries for sequences related to 3x+1 (or Collatz) problem

FORMULA

a(n) = floor(A225761(n)/A225784(n)).

PROG

(Haskell)

a225843 = floor . sum . map (recip . fromIntegral) . a070165_row

CROSSREFS

Sequence in context: A035164 A023588 A175242 * A001227 A060764 A105149

Adjacent sequences:  A225840 A225841 A225842 * A225844 A225845 A225846

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 16 2013

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified February 21 14:40 EST 2018. Contains 299414 sequences. (Running on oeis4.)