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 A296207 #11 Dec 26 2017 18:03:41 %S A296207 0,1,1,2,1,0,1,4,3,6,1,0,1,4,7,8,1,12,1,12,5,8,1,0,5,14,9,8,1,6,1,16, %T A296207 9,18,3,24,1,16,15,24,1,26,1,16,5,20,1,0,7,22,19,28,1,0,15,16,17,30,1, %U A296207 12,1,28,31,32,9,58,1,36,21,38,1,48,1,38,19,32,13,54,1,48,27,42,1,52,21,40,31,32,1,34,11,40,29,44,23,0,1 %N A296207 Xor-Moebius transform of A227320, binary XOR of proper divisors of n. %C A296207 Unique sequence satisfying SumXOR_{d divides n} a(d) = A227320(n) for all n > 0, where SumXOR is the analog of summation under the binary XOR operation. See A295901 for a list of some of the properties of Xor-Moebius transform. %H A296207 Antti Karttunen, <a href="/A296207/b296207.txt">Table of n, a(n) for n = 1..16384</a> %H A296207 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a> %F A296207 a(n) = n XOR A256739(n), where XOR is the bitwise XOR-operation (A003987). %o A296207 (PARI) %o A296207 A227320(n) = { my(s=0); fordiv(n,d,if(d<n,s = bitxor(s,d))); s; }; %o A296207 A296207(n) = { my(v=0); fordiv(n, d, if(issquarefree(n/d), v=bitxor(v, A227320(d)))); (v); } \\ after code in A295901. %Y A296207 Cf. A003987, A178910, A227320, A256739, A295901, A296206. %Y A296207 Cf. A297107 (positions of zeros). %K A296207 nonn,base %O A296207 1,4 %A A296207 _Antti Karttunen_, Dec 25 2017