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A211408
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
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, 58, 66, 67, 69, 76, 77, 79, 83, 84, 85, 88, 96, 97, 99, 101, 102, 103, 104, 105, 106, 107, 108, 109, 111, 112, 113, 115, 118, 121, 122, 123, 124, 125, 126, 127, 128, 129
OFFSET
0,3
COMMENTS
All base-10 palindromes occur in this sequence.
LINKS
FORMULA
{n such that A005589(n) = A005589(A004086(n))}.
EXAMPLE
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).
14 is in the sequence because "fourteen" and "fortyone" both have 8 letters.
MATHEMATICA
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 *)
CROSSREFS
Subsequences: A002113.
Sequence in context: A061430 A065448 A254656 * A107322 A194975 A299441
KEYWORD
nonn,base,easy,word
AUTHOR
Jonathan Vos Post, Feb 09 2013
EXTENSIONS
Corrected and extended by Robert G. Wilson v, Feb 12 2013
STATUS
approved