A077406 -id:A077406 - cp's OEIS frontend

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.

0, 2, 11, 19, 20, 74, 398, 779, 1062, 2329, 4189, 4280, 11278, 19962, 98318, 135137, 1051360, 1592930, 69226926, 4295054186, 4446008678, 17187271449, 18123849698

Offset: 1

Klaus Brockhaus, Dec 08 2001

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.

			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.

Index entries for sequences related to Reverse and Add!

Record setting values in base b: A077406 (b=3), A075686 (b=4), A306599 (b=8), A065198 (b=10), A348571 (Zeckendorf).

Cf. A062130, A066057, A066058, A066059, A066145.

limit = 10^4; (* Assumes that there is no palindrome if none is found before "limit" iterations *)
best = -1; Select[Range[0, 100000], (np = #; i = 0;
   While[np != IntegerReverse[np, 2] && i < limit,
    np = np + IntegerReverse[np, 2]; i++];
If[i >= limit, False, If[i > best, best = i; True]]) &] (* Robert Price, Oct 14 2019 *)

Offset corrected and a(19)-a(23) from A.H.M. Smeets, Apr 30 2022

A077407 In base 3, records for the number of Reverse and Add! steps needed to reach a palindrome.

Original entry on oeis.org

0, 1, 2, 3, 4, 18, 20, 21, 27, 28, 55, 56, 57, 70

Offset: 1

Klaus Brockhaus, Nov 05 2002

RECORDS transform of A077402. Base-3 analog of A066145 (base 2), A075687 (base 4) and A065199 (base 10). A077406 gives the corresponding starting points.

Probable Lychrel numbers are ignored, the first of which is 103. - Sean A. Irvine, Apr 19 2010

			Starting with 15, 3 Reverse and Add! steps are needed to reach a palindrome; starting with n < 15, less (at most 2) steps are needed.

N. J. A. Sloane, Transforms
Index entries for sequences related to Reverse and Add!

Cf. A065199, A066145, A075687, A077402, A077406.

a(14) from Sean A. Irvine, Apr 19 2010

cp's OEIS Frontend

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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