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A158642 Palindromic numbers which are the product of a number n and its reversal (n written backwards) 2

%I #6 Aug 24 2012 10:50:02

%S 0,1,4,9,121,252,484,10201,12321,14641,20502,23632,26962,40804,44944,

%T 1002001,1113111,1226221,1234321,1357531,2005002,2126212,2216122,

%U 2249422,2347432,2429242,4008004,4229224,100020001

%N Palindromic numbers which are the product of a number n and its reversal (n written backwards)

%C Apart from 3 which produces 9 (3*3), all the other numbers n which satisfy the definition are formed by digits 0, 1 and 2 only. Subset of A002113.

%C Every term has an odd number of digits. - Floris van Doorn, Sep 25 2009

%H Floris P. van Doorn, <a href="/A158642/b158642.txt">Table of n, a(n) for n=0,...,10126</a> (every term with at most 27 digits)

%e 0*0=0; 1*1=1; 2*2=4; 3*3=9; 11*11=121; 12*21=252; 22*22=484; 101*101=10201; 102*201=20502; etc.

%Y Cf. A002113

%K easy,nonn,base

%O 0,3

%A _Paolo P. Lava_ and _Giorgio Balzarotti_, Mar 23 2009

%E Corrected by _Floris P. van Doorn_, Sep 25 2009

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Last modified April 18 03:01 EDT 2024. Contains 371767 sequences. (Running on oeis4.)