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 A292389 #17 Aug 17 2025 21:10:55
%S A292389 2,3,7,2,5,3,11,2,13,7,11,5,23,7,19,2,17,7,31,5,37,59,31,3,37,7,47,5,
%T A292389 41,2,23,37,2,31,47,2,29,41,7,61,11,53,2,43,19,47,109,41,97,43,107,37,
%U A292389 113,61,2,59,107,61,101,59,97,61,89,31,127,29,79,2,67
%N A292389 a(n) = SumXOR_{k=1..n} A292388(k) (where SumXOR is the analog of summation under the binary XOR operation).
%C A292389 All terms are prime.
%C A292389 Conjecturally, this sequence contains infinitely many 2's.
%H A292389 Rémy Sigrist, <a href="/A292389/b292389.txt">Table of n, a(n) for n = 1..10000</a>
%e A292389 a(3) = A292388(1) XOR A292388(2) XOR A292388(3) = 2 XOR 1 XOR 4 = 7.
%o A292389 (PARI) s=0; x=0; for (n=1, 69, for (v=1, oo, if (!bittest(s,v) && isprime(bitxor(x,v)), s+=2^v; x=bitxor(x,v); print1 (x ", "); break)))
%Y A292389 Cf. A292388.
%K A292389 nonn,base,look
%O A292389 1,1
%A A292389 _Rémy Sigrist_, Sep 15 2017