%I #41 Sep 14 2024 13:31:55

%S 89,98,187,286,385,583,682,781,869,880,968,1297,1387,1477,1567,1657,

%T 1747,1837,1927,2296,2386,2476,2566,2656,2746,2836,2926,3295,3385,

%U 3475,3565,3655,3745,3835,3925,4294,4384,4474,4564,4654,4744,4834,4924,5293,5383

%N Numbers whose "reverse and add" process becomes palindromic at 8813200023188.

%C The "reverse and add" sequence for 178 includes 8813200023188, but it becomes palindromic at 15851, so 178 is not in this sequence.

%C See interesting patterns of the first differences in A328492. - _Robert Price_, Oct 16 2019

%D David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987. See p. 143.

%H Daniel Starodubtsev, <a href="/A240510/b240510.txt">Table of n, a(n) for n = 1..100000</a> (terms 1..177 from Robert Price)

%H Felix Fröhlich, <a href="/A240510/a240510.txt">C++ program for this sequence</a>.

%t limit = 10^3; (* Assumes that there is no palindrome if none is found before "limit" iterations *)

%t Select[Range[0, 50000], (np = #; i = 0;

%t While[ ! PalindromeQ[np] && i < limit,

%t np = np + IntegerReverse[np]; i++];

%t np == 8813200023188) &] (* _Robert Price_, Oct 16 2019 *)

%o (PARI) is(n)=my(k=8813200023188); while(n<=k && (d=digits(n))!=(r=Vecrev(d)), n+=fromdigits(r)); n==k; \\ _Charles R Greathouse IV_, Apr 09 2020

%Y Cf. A033670, A328492.

%K base,nonn,fini

%O 1,1

%A _J. Lowell_, Apr 06 2014

%E More terms from _Jon E. Schoenfield_, Apr 12 2014