cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A066144 In base 2: n sets a new record for the number of 'Reverse and Add' steps needed to reach a palindrome starting with n.

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%I A066144 #25 May 16 2022 16:20:19
%S A066144 0,2,11,19,20,74,398,779,1062,2329,4189,4280,11278,19962,98318,135137,
%T A066144 1051360,1592930,69226926,4295054186,4446008678,17187271449,
%U A066144 18123849698
%N A066144 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 A066144 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 A066144 <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>
%e A066144 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 A066144 limit = 10^4; (* Assumes that there is no palindrome if none is found before "limit" iterations *)
%t A066144 best = -1; Select[Range[0, 100000], (np = #; i = 0;
%t A066144    While[np != IntegerReverse[np, 2] && i < limit,
%t A066144     np = np + IntegerReverse[np, 2]; i++];
%t A066144 If[i >= limit, False, If[i > best, best = i; True]]) &] (* _Robert Price_, Oct 14 2019 *)
%Y A066144 Record setting values in base b: A077406 (b=3), A075686 (b=4), A306599 (b=8), A065198 (b=10), A348571 (Zeckendorf).
%Y A066144 Cf. A062130, A066057, A066058, A066059, A066145.
%K A066144 nonn,base,more
%O A066144 1,2
%A A066144 _Klaus Brockhaus_, Dec 08 2001
%E A066144 Offset corrected and a(19)-a(23) from _A.H.M. Smeets_, Apr 30 2022