The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
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!)
A041013 Reverse or double: if reverse of a(n) > a(n), then a(n+1) = a(n) reversed, otherwise a(n+1) = 2*a(n). 1
1, 2, 4, 8, 16, 61, 122, 221, 442, 884, 1768, 8671, 17342, 24371, 48742, 97484, 194968, 869491, 1738982, 2898371, 5796742, 11593484, 48439511, 96879022, 193758044, 440857391, 881714782, 1763429564, 4659243671, 9318487342, 18636974684, 48647963681 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
MATHEMATICA
rd[n_]:=Module[{rev=FromDigits[Reverse[IntegerDigits[n]]]}, If[ rev>n, rev, 2n]]; NestList[rd, 1, 40] (* Harvey P. Dale, Jan 25 2013 *)
NestList[If[IntegerReverse[#]>#, IntegerReverse[#], 2#]&, 1, 40] (* Harvey P. Dale, Aug 23 2023 *)
PROG
(Haskell)
a041013 n = a041013_list !! n
a041013_list = 1 : f 1 where
f x | rev <= x = (2*x) : f (2*x)
| otherwise = rev : f rev where rev = a004086 x
-- Reinhard Zumkeller, Aug 08 2011
CROSSREFS
Cf. A004086.
Sequence in context: A018681 A367172 A018735 * A018754 A264980 A318151
KEYWORD
base,nonn,nice
AUTHOR
EXTENSIONS
Typo in definition corrected by K. Viswanathan Iyer, Mar 23 2010
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 May 21 15:23 EDT 2024. Contains 372738 sequences. (Running on oeis4.)