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 A325315 #16 Apr 22 2019 13:49:39 %S A325315 1,3,2,1,4,0,6,1,5,2,10,4,12,4,6,1,16,15,18,6,30,24,22,20,19,10,30,0, %T A325315 28,52,30,1,46,54,46,51,36,48,54,54,40,28,42,12,28,52,46,100,41,57,38, %U A325315 14,52,28,38,8,46,26,58,40,60,28,22,1,82,12,66,10,94,12,70,83,72,98,42,20,94,20,78,102,105,126,82,32,66,120,118,12 %N A325315 Bitwise-XOR of absolute values of (n - A048250(n)) and (n - A162296(n)). %H A325315 Antti Karttunen, <a href="/A325315/b325315.txt">Table of n, a(n) for n = 1..65537</a> %H A325315 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a> %H A325315 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a> %F A325315 a(n) = A003987(abs(A325313(n)), abs(A325314(n))). %t A325315 Array[BitXor @@ Abs[#1 - Map[Total, {#3, Complement[#2, #3]}]] & @@ {#1, #2, Select[#2, SquareFreeQ]} & @@ {#, Divisors[#]} &, 88] (* _Michael De Vlieger_, Apr 21 2019 *) %o A325315 (PARI) %o A325315 A048250(n) = factorback(apply(p -> p+1,factor(n)[,1])); %o A325315 A325313(n) = (A048250(n) - n); %o A325315 A162296(n) = sumdiv(n, d, d*(1-issquarefree(d))); %o A325315 A325314(n) = (n - A162296(n)); %o A325315 A325315(n) = bitxor(abs(A325313(n)),abs(A325314(n))); %Y A325315 Cf. A000396, A003987, A028982 (positions of odd terms), A048250, A162296, A228058, A325310, A325313, A325314. %K A325315 nonn %O A325315 1,2 %A A325315 _Antti Karttunen_, Apr 21 2019