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Numbers k such that the number of letters, excluding spaces and hyphens, in the English names of k and its reversal are the same.
1

%I #23 Oct 26 2024 22:57:34

%S 0,1,2,3,4,5,6,7,8,9,10,11,14,22,33,34,35,38,41,43,44,45,48,53,54,55,

%T 58,66,67,69,76,77,79,83,84,85,88,96,97,99,101,102,103,104,105,106,

%U 107,108,109,111,112,113,115,118,121,122,123,124,125,126,127,128,129

%N Numbers k such that the number of letters, excluding spaces and hyphens, in the English names of k and its reversal are the same.

%C All base-10 palindromes occur in this sequence.

%H Robert G. Wilson v, <a href="/A211408/b211408.txt">Table of n, a(n) for n = 0..23885</a>

%F {n such that A005589(n) = A005589(A004086(n))}.

%e 10 is in the sequence because "ten" has three letters, and so does "one" which is the name of the digital reverse of 10, which is 1 (because the leading 0 is truncated in 01).

%e 14 is in the sequence because "fourteen" and "fortyone" both have 8 letters.

%t lst= {(* copy the words from https://oeis.org/A000027/a000027.txt *)}; f[n_] := StringLength@ ToString@ lst[[n + 1]]; fQ[n_] := f@ n == f@ FromDigits@ Reverse@ IntegerDigits@ n; Select[Range[0, 130], fQ] (* _Robert G. Wilson v_, Feb 12 2013 *)

%Y Subsequences: A002113.

%Y Cf. A000027, A004086, A005589, A107322.

%K nonn,base,easy,word,changed

%O 0,3

%A _Jonathan Vos Post_, Feb 09 2013

%E Corrected and extended by _Robert G. Wilson v_, Feb 12 2013