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A048344
a(n) * a(n)_reversed is a palindrome (and a(n) is not palindromic).
3
12, 21, 102, 112, 122, 201, 211, 221, 1002, 1011, 1012, 1021, 1022, 1101, 1102, 1112, 1121, 1201, 1202, 1211, 2001, 2011, 2012, 2021, 2101, 2102, 2111, 2201, 10002, 10011, 10012, 10021, 10022, 10102, 10111, 10112, 10121, 10202, 10211, 11001
OFFSET
1,1
COMMENTS
Does any term in this sequence have any digit greater than 2? [From Harvey P. Dale, Nov 05 2011]
EXAMPLE
E.g. 10021 x 12001 = 120262021 is a palindrome.
MATHEMATICA
palQ[n_]:=Module[{idn=IntegerDigits[n], ridn, idn2}, ridn=Reverse[idn]; idn2 = IntegerDigits[ n FromDigits[ridn]]; idn!=ridn&&idn2==Reverse[idn2]]; Select[ Range[11100], palQ] (* Harvey P. Dale, Nov 05 2011 *)
Select[Range[12000], !PalindromeQ[#]&&PalindromeQ[# IntegerReverse[#]]&] (* Harvey P. Dale, Jul 10 2023 *)
PROG
(Haskell)
a048344 n = a048344_list !! (n-1)
a048344_list = filter f a029742_list where
f x = a136522 (x * a004086 x) == 1
-- Reinhard Zumkeller, Oct 09 2011
(Python)
A048344_list = []
for n in range(1, 10**5):
....s = str(n)
....s2 = str(n)[::-1]
....if s != s2:
........s3 = str(n*int(s2))
........if s3 == s3[::-1]:
............A048344_list.append(n) # Chai Wah Wu, Sep 08 2014
CROSSREFS
KEYWORD
nonn,base,nice
AUTHOR
Patrick De Geest, Feb 15 1999
EXTENSIONS
Offset corrected by Reinhard Zumkeller, Oct 09 2011
STATUS
approved