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.
%I A217557 #25 Mar 20 2013 19:37:27
%S A217557 0,127,62,189,28,155,90,217,8,135,70,197,36,163,98,225,-8,119,54,181,
%T A217557 20,147,82,209,0,127,62,189,28,155,90,217,-28,99,34,161,0,127,62,189,
%U A217557 -20,107,42,169,8,135,70,197,-36,91,26,153,-8,119,54,181,-28,99
%N A217557 The difference between the reversal of an 8-bit integer and the original integer.
%C A217557 The difference between the reversal of an 8-bit integer and the original integer.
%H A217557 Vincenzo Librandi, <a href="/A217557/b217557.txt">Table of n, a(n) for n = 0..255</a> (all terms of the sequence).
%F A217557 a(n) = A160638(n) - n.
%e A217557 5 -> 00000101 -> 10100000 = 160 so a(5) = 155.
%t A217557 Table[FromDigits[Reverse[PadLeft[IntegerDigits[n,2],8,0]],2]-n,{n,0,60}] (* _Harvey P. Dale_, Oct 12 2012 *)
%o A217557 (PARI) A217557(n)=sum(i=0,7,bittest(n,7-i)<<i)-n \\ - _M. F. Hasler_, Oct 07 2012
%Y A217557 Cf. A160638.
%K A217557 sign,base,fini,full
%O A217557 0,2
%A A217557 _Jon Perry_, Oct 06 2012