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{n concatenate R(n)}*{ R(n) concatenate n}, where R(n) = digit reversal of n.
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%I #10 Sep 06 2017 21:18:07

%S 0,121,484,1089,1936,3025,4356,5929,7744,9801,110110,1234321,2578752,

%T 4143403,5928274,7933365,10158676,12604207,15269958,18155929,440440,

%U 2578752,4937284,7516036,10315008,13334200,16573612,20033244,23713096

%N {n concatenate R(n)}*{ R(n) concatenate n}, where R(n) = digit reversal of n.

%C a(n) == 0 (mod 11)

%H G. C. Greubel, <a href="/A110722/b110722.txt">Table of n, a(n) for n = 0..1000</a>

%F When n has one digit a(n)=(11n)^2. When n has two digits a(n)= 110110*x^2 + 1014101*x*y + 110110*y^2. (Here x,y are the digits of n.). - _Keith Schneider_, Jun 16 2007

%e a(13) = 1331*3113 = 4143403.

%t Table[FromDigits[Join[IntegerDigits[n], Reverse[IntegerDigits[n]]]]* FromDigits[Join[Reverse[IntegerDigits[n]], IntegerDigits[n]]], {n, 0, 50}] (* _G. C. Greubel_, sep 06 2017 *)

%K base,easy,nonn

%O 0,2

%A _Amarnath Murthy_, Aug 09 2005

%E More terms from Maire B. O'Neill (mbo5001(AT)psu.edu), Sep 18 2005

%E Corrected by James Greene (jmg482(AT)psu.edu), Apr 07 2006