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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A211518 a(n) is the sum of all distinct integers that can be produced by reversing the digits of n in any base b >= 2.

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%I A211518 #25 May 13 2013 01:54:21
%S A211518 1,3,4,5,13,21,37,40,71,82,150,140,232,252,327,352,520,497,711,729,
%T A211518 881,1027,1325,1214,1567,1700,1904,2016,2388,2523,2997,3178,3583,3758,
%U A211518 4406,4244,5138,5379,6055,5948,6988,7027,8150,8240,8971,9303,10476,10441,11808,12088,13139,13571,15009,15047,16473,16620,18263,19020
%N A211518 a(n) is the sum of all distinct integers that can be produced by reversing the digits of n in any base b >= 2.
%H A211518 Charles R Greathouse IV, <a href="/A211518/b211518.txt">Table of n, a(n) for n = 1..10000</a>
%e A211518 If n=3, we can get 3 from base 10 (or any other base except 3) and 1 from reversing the base-3 expansion 10, so a(3) = 3+1 = 4.
%t A211518 rev[x_,b_]:=FromDigits[Reverse[IntegerDigits[x,b]],b];Total/@Union/@Table[Table[rev[x,b],{b,2,x+1}],{x,Startpoint,Endpoint}]
%o A211518 (PARI) rev(n,B)=my(m=n%B);n\=B;while(n>0,m=m*B+n%B;n\=B);m
%o A211518 a(n)=if(n<3,2*n-1,my(v=vecsort(vector(n-1,k,rev(n,k+1)),,8));sum(i=1,#v,v[i])) \\ _Charles R Greathouse IV_, Aug 05 2012
%K A211518 nonn,base
%O A211518 1,2
%A A211518 _Dylan Hamilton_, Jun 26 2012