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%I #25 May 16 2022 16:20:19
%S 0,2,11,19,20,74,398,779,1062,2329,4189,4280,11278,19962,98318,135137,
%T 1051360,1592930,69226926,4295054186,4446008678,17187271449,
%U 18123849698
%N In base 2: n sets a new record for the number of 'Reverse and Add' steps needed to reach a palindrome starting with n.
%C The analog of A065198 in base 2. Integers like 22, for which a palindrome is never reached (cf. A066059), are of course disregarded. A066145 gives the corresponding records.
%H <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>
%e Starting with 74, 11 'Reverse and Add' steps are needed to reach a palindrome; starting with n < 74, less (at most 5) steps are needed.
%t limit = 10^4; (* Assumes that there is no palindrome if none is found before "limit" iterations *)
%t best = -1; Select[Range[0, 100000], (np = #; i = 0;
%t While[np != IntegerReverse[np, 2] && i < limit,
%t np = np + IntegerReverse[np, 2]; i++];
%t If[i >= limit, False, If[i > best, best = i; True]]) &] (* _Robert Price_, Oct 14 2019 *)
%Y Record setting values in base b: A077406 (b=3), A075686 (b=4), A306599 (b=8), A065198 (b=10), A348571 (Zeckendorf).
%Y Cf. A062130, A066057, A066058, A066059, A066145.
%K nonn,base,more
%O 1,2
%A _Klaus Brockhaus_, Dec 08 2001
%E Offset corrected and a(19)-a(23) from _A.H.M. Smeets_, Apr 30 2022
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