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A029742
Nonpalindromic numbers.
34
10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 100, 102, 103, 104, 105, 106, 107
OFFSET
1,1
COMMENTS
Complement of A002113; A136522(a(n)) = 0.
A064834(a(n)) > 0. - Reinhard Zumkeller, Sep 18 2013
MATHEMATICA
palQ[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]]; DeleteCases[ Range[10, 110], _?palQ] (* Harvey P. Dale, Jan 28 2012 *)
Table[If[PalindromeQ[n], Nothing, n], {n, 120}] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 13 2019 *)
PROG
(Haskell)
a029742 n = a029742_list !! (n-1)
a029742_list = filter ((== 0) . a136522) [1..]
-- Reinhard Zumkeller, Oct 09 2011
(Magma) [n: n in [0..150] | Intseq(n) ne Reverse(Intseq(n))]; // Bruno Berselli, Apr 01 2015
(PARI) is(n)=my(d=digits(n)); d!=Vecrev(d) \\ Charles R Greathouse IV, Feb 06 2017
(Python)
def ok(n): s = str(n); return s != s[::-1]
print(list(filter(ok, range(108)))) # Michael S. Branicky, Oct 12 2021
(Python)
def A029742(n):
def f(x): return n+x//10**((l:=len(s:=str(x)))-(k:=l+1>>1))-(int(s[k-1::-1])>x%10**k)+10**(k-1+(l&1^1))-1
m, k = n, f(n)
while m != k:
m, k = k, f(k)
return m # Chai Wah Wu, Jul 24 2024
CROSSREFS
Cf. A002113. Different from A031955.
Sequence in context: A139819 A288040 A031955 * A043638 A280824 A329448
KEYWORD
nonn,base,easy,nice
EXTENSIONS
Offset corrected by Reinhard Zumkeller, Oct 09 2011
STATUS
approved