A292389 - OEIS

%I #10 Sep 21 2017 18:04:01

%S 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 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 113,61,2,59,107,61,101,59,97,61,89,31,127,29,79,2,67

%N a(n) = SumXOR_{k=1..n} A292388(k) (where SumXOR is the analog of summation under the binary XOR operation).

%C All terms are prime.

%C Conjecturally, this sequence contains infinitely many 2's.

%H Rémy Sigrist, <a href="/A292389/b292389.txt">Table of n, a(n) for n = 1..10000</a>

%e a(3) = A292388(1) XOR A292388(2) XOR A292388(3) = 2 XOR 1 XOR 4 = 7.

%o (PARI) s=0; x=0; for (n=1, 69, for (v=1, oo, if (!bit test(s,v) && is prime(bit xor(x,v)), s+=2^v; x=bit xor(x,v); print1 (x ", "); break)))

%Y Cf. A292388.

%K nonn,base,look

%O 1,1

%A _Rémy Sigrist_, Sep 15 2017