The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A023109 Smallest number that requires exactly n iterations of Reverse and Add to reach a palindrome. 34
 0, 10, 19, 59, 69, 166, 79, 188, 193, 1397, 829, 167, 2069, 1797, 849, 177, 1496, 739, 1798, 10777, 6999, 1297, 869, 187, 89, 10797, 10853, 10921, 10971, 13297, 10548, 13293, 17793, 20889, 700269, 106977, 108933, 80359, 13697, 10794, 15891, 1009227, 1007619, 1009246, 1008628, 600259, 131996, 70759, 1007377, 1001699, 600279, 141996, 70269, 10677, 10833, 10911 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Chai Wah Wu, Table of n, a(n) for n = 0..100 Jason Doucette, World Records Eric Weisstein's World of Mathematics, 196-Algorithm. MATHEMATICA Table[ SelectFirst[Range[0, 20000], (np = #; i = 0;     While[ ! PalindromeQ[np] && i <= n, np = np + IntegerReverse[np];      i++]; i == n ) &] , {n, 0, 32}] (* Robert Price, Oct 16 2019 *) PROG (PARI) rev(n)={d=digits(n); p=""; for(i=1, #d, p=concat(Str(d[i]), p)); return(eval(p))} a(n)=if(n==rev(n), return(0)); for(k=1, 10^3, i=n+rev(n); if(rev(i)==i, return(k)); n=i) b(n)=for(k=1, 10^8, if(a(k)==n, return(k))) n=0; while(n<100, print1(b(n), ", "); n++) \\ Derek Orr, Jul 28 2014 (Python) def A023109(n):     if n > 0:         k = 0         while True:             m = k             for i in range(n):                 if str(m) == str(m)[::-1]:                     break                 m += int(str(m)[::-1])             else:                 if str(m) == str(m)[::-1]:                     return k             k += 1     else:         return 0 # Chai Wah Wu, Feb 08 2015 CROSSREFS Cf. A033665, A006960. Sequence in context: A330570 A065198 A033866 * A255530 A146091 A007811 Adjacent sequences:  A023106 A023107 A023108 * A023110 A023111 A023112 KEYWORD nonn,base,nice AUTHOR EXTENSIONS Verified and added terms a(41)-a(55) by Aldo González Lorenzo, May 15 2011 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 19 02:54 EDT 2020. Contains 337175 sequences. (Running on oeis4.)