OFFSET
0,3
COMMENTS
Also called digit reversal of n.
Leading zeros (after the reversal has taken place) are omitted. - N. J. A. Sloane, Jan 23 2017
For n>0: a(a(n)) = n iff n mod 10 != 0. - Reinhard Zumkeller, Mar 10 2002
LINKS
Indranil Ghosh, Table of n, a(n) for n = 0..50000 (first 1001 terms from Franklin T. Adams-Watters)
Dana G. Korssjoen, Biyao Li, Stefan Steinerberger, Raghavendra Tripathi, and Ruimin Zhang, Finding structure in sequences of real numbers via graph theory: a problem list, arXiv:2012.04625 [math.CO], Dec 08 2020.
Michael Penn, A digit moving number puzzle., YouTube video, 2022.
FORMULA
a(n) = d(n,0) with d(n,r) = if n=0 then r, otherwise d(floor(n/10), r*10+(n mod 10)). - Reinhard Zumkeller, Mar 04 2010
a(10*n+x) = x*10^m + a(n) if 10^(m-1) <= n < 10^m and 0 <= x <= 9. - Robert Israel, Jun 11 2015
MAPLE
read transforms; A004086 := digrev; #cf "Transforms" link at bottom of page
A004086:=proc(n) local s, t; if n<10 then n else s:=irem(n, 10, 't'); while t>9 do s:=s*10+irem(t, 10, 't') od: s*10+t fi end; # M. F. Hasler, Jan 29 2012
MATHEMATICA
Table[FromDigits[Reverse[IntegerDigits[n]]], {n, 0, 75}]
IntegerReverse[Range[0, 80]](* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 13 2018 *)
PROG
(PARI) dig(n) = {local(m=n, r=[]); while(m>0, r=concat(m%10, r); m=floor(m/10)); r}
A004086(n) = {local(b, m, r); r=0; b=1; m=dig(n); for(i=1, matsize(m)[2], r=r+b*m[i]; b=b*10); r} \\ Michael B. Porter, Oct 16 2009
(PARI) A004086(n)=fromdigits(Vecrev(digits(n))) \\ M. F. Hasler, Nov 11 2010, updated May 11 2015, Sep 13 2019
(Haskell) a004086 = read . reverse . show -- Reinhard Zumkeller, Apr 11 2011
(Python)
def A004086(n):
return int(str(n)[::-1]) # Chai Wah Wu, Aug 30 2014
(J) |.&.": i.@- 1e5 NB. Stephen Makdisi, May 14 2018
CROSSREFS
KEYWORD
AUTHOR
EXTENSIONS
Extended by Ray Chandler, Dec 30 2004
STATUS
approved