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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Does any term in this sequence have any digit greater than 2? [From Harvey P. Dale, Nov 05 2011]

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

P. De Geest, Palindromic Products of Non Palindromic Integers and their Reversals

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 *)

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

Cf. A048343.

Cf. A004086, A136522, A029742.

Sequence in context: A228766 A157157 A218043 * A039402 A043225 A111066

Adjacent sequences:  A048341 A048342 A048343 * A048345 A048346 A048347

KEYWORD

nonn,base,nice

AUTHOR

Patrick De Geest, Feb 15 1999

EXTENSIONS

Offset corrected by Reinhard Zumkeller, Oct 09 2011

STATUS

approved

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Last modified August 24 04:54 EDT 2017. Contains 291052 sequences.