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!)
A109867 a(1) = 12; for n >= 1, a(n+1) = {a(n)+R(a(n)}*{a(n)-R(a(n)}, where R(k) is the digit reversal of k. 0
12, 297, 539055, 12949081200, 167631138529627443759, 888408727567955042239409874101472777521040, 787659989217062162749912989661115208857840881836480202901460330472578518132645989056 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The next term has 168 digits. - Harvey P. Dale, Dec 01 2017

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

a(2) = (12 + 21)*(21 - 12) = 297.

MATHEMATICA

a = {12}; For[n = 2, n < 10, n++, AppendTo[a, Abs[(a[[ -1]] + FromDigits[Reverse[IntegerDigits[a[[ -1]]]]])* (a[[ -1]] - FromDigits[Reverse[IntegerDigits[a[[ -1]]]]])]]]; a (* Stefan Steinerberger, Jun 05 2007 *)

NestList[(#+IntegerReverse[#])Abs[#-IntegerReverse[#]]&, 12, 10] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Dec 01 2017 *)

CROSSREFS

Sequence in context: A220307 A223011 A245915 * A326437 A303068 A014130

Adjacent sequences:  A109864 A109865 A109866 * A109868 A109869 A109870

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Jul 09 2005

EXTENSIONS

Corrected and extended by Stefan Steinerberger, Jun 05 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 July 3 13:57 EDT 2022. Contains 355055 sequences. (Running on oeis4.)