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A061205 a(n) = n times R(n) where R(n) (A004086) is the digit reversal of n.

%I A061205 #53 Dec 06 2024 21:44:07
%S A061205 0,1,4,9,16,25,36,49,64,81,10,121,252,403,574,765,976,1207,1458,1729,
%T A061205 40,252,484,736,1008,1300,1612,1944,2296,2668,90,403,736,1089,1462,
%U A061205 1855,2268,2701,3154,3627,160,574,1008,1462,1936,2430,2944,3478,4032,4606
%N A061205 a(n) = n times R(n) where R(n) (A004086) is the digit reversal of n.
%C A061205 Every third term is divisible by 9, no other term is divisible by 3. - _Alonso del Arte_, Mar 04 2013
%H A061205 Harry J. Smith and Indranil Ghosh, <a href="/A061205/b061205.txt">Table of n, a(n) for n = 0..10000</a> (first 1001 terms from Harry J. Smith)
%e A061205 a(10) = 10 = 10 * 01.
%e A061205 a(11) = 121 = 11 * 11.
%e A061205 a(12) = 252 = 12 * 21.
%e A061205 a(13) = 403 = 13 * 31.
%t A061205 #*FromDigits[Reverse[IntegerDigits[#]]] &/@Range[0, 49]  (* _Ant King_, Jan 07 2012 *)
%t A061205 #*IntegerReverse[#]& /@ Range[0, 49] (* _Jean-François Alcover_, Oct 27 2019 *)
%o A061205 (PARI) rev(k) = subst(Polrev(digits(k)), x, 10);
%o A061205 a(n) = n*rev(n); \\ _Michel Marcus_, Feb 14 2015
%o A061205 (PARI) a(n) = n*fromdigits(Vecrev(digits(n))); \\ _Michel Marcus_, May 28 2018
%o A061205 (Haskell)
%o A061205 a061205 n = a004086 n * n
%o A061205 -- _Reinhard Zumkeller_, Apr 10 2012, Apr 29 2011
%o A061205 (Python)
%o A061205 def A061205(n):
%o A061205     return n*A004086(n) # _Indranil Ghosh_, Jan 09 2017
%Y A061205 Cf. A004086, A203924 (triple repetitions).
%K A061205 nonn,base,look
%O A061205 0,3
%A A061205 _Amarnath Murthy_, Apr 21 2001
%E A061205 Corrected and extended by _Patrick De Geest_, Jun 04 2001