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A056964 a(n) = n + reversal of digits of n.

%I A056964 #57 Jul 31 2025 16:12:10
%S A056964 0,2,4,6,8,10,12,14,16,18,11,22,33,44,55,66,77,88,99,110,22,33,44,55,
%T A056964 66,77,88,99,110,121,33,44,55,66,77,88,99,110,121,132,44,55,66,77,88,
%U A056964 99,110,121,132,143,55,66,77,88,99,110,121,132,143,154,66,77,88,99,110
%N A056964 a(n) = n + reversal of digits of n.
%C A056964 If n has an even number of digits then a(n) is a multiple of 11.
%C A056964 Also called the Reverse and Add!, or RADD operation. Iteration of this function leads to the definition of Lychrel and related numbers, cf. A023108, A063048, A088753, A006960, and many others. - _M. F. Hasler_, Apr 13 2019
%H A056964 Indranil Ghosh, <a href="/A056964/b056964.txt">Table of n, a(n) for n = 0..20000</a> (first 1001 terms from T. D. Noe)
%H A056964 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Reverse-Then-AddSequence.html">Reverse-Then-Add Sequence</a>
%H A056964 <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>
%F A056964 a(n) = n + A004086(n) = 2*n - A056965(n).
%F A056964 n < a(n) < 11n for n > 0. - _Charles R Greathouse IV_, Nov 17 2022
%e A056964 a(17) = 17 + 71 = 88.
%t A056964 Table[n+FromDigits[Reverse[IntegerDigits[n]]],{n,0,100}] (* _Harvey P. Dale_, Jul 19 2014 *)
%t A056964 #+IntegerReverse[#]&/@Range[0,100] (* _Harvey P. Dale_, Jul 31 2025 *)
%o A056964 (Haskell) a056964 n = n + a004086 n  -- _Reinhard Zumkeller_, Oct 14 2011
%o A056964 (PARI) A056964(n)=fromdigits(Vecrev(digits(n)))+n \\ _Charles R Greathouse IV_, Oct 28 2014
%o A056964 (Python) def A056964(n): return n+int(str(n)[::-1]) # _Indranil Ghosh_, Jan 29 2017
%Y A056964 Cf. A004086, A056965, A067030.
%Y A056964 Differs from A052008 when n=101 and a(101)=202 while A052008(101)=121
%Y A056964 Cf. A036839.
%K A056964 nonn,base,easy
%O A056964 0,2
%A A056964 _Henry Bottomley_, Jul 18 2000