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a(n) = bitwise XOR of decimal digits of primes.
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%I #23 Jul 26 2021 06:53:11

%S 2,3,5,7,0,2,6,8,1,11,2,4,5,7,3,6,12,7,1,6,4,14,11,1,14,0,2,6,8,3,4,3,

%T 5,11,12,5,3,4,0,5,15,8,9,11,15,1,2,3,7,9,2,8,7,6,0,7,13,4,2,11,9,8,4,

%U 3,1,5,1,7,0,14,5,15,2,7,13,8,2,13,5,13,12

%N a(n) = bitwise XOR of decimal digits of primes.

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Bitwise operation">Bitwise operation</a>

%p b:= l-> `if`(l=[], 0, Bits[Xor](l[1], b(subsop(1=[][], l)))):

%p a:= n-> b(convert(ithprime(n), base, 10)):

%p seq(a(n), n=1..82); # _Alois P. Heinz_, Jul 21 2021

%t Table[BitXor @@ IntegerDigits[Prime[n]], {n, 1, 100}] (* _Amiram Eldar_, Jul 21 2021 *)

%o (Sage)

%o def XOR(a, b):

%o return a ^^ b

%o [reduce(XOR, map(lambda x: int(x), str(p))) for p in (0..100) if p in Primes()]

%o (PARI) a(n) = my(d=digits(prime(n)), k=0); for (i=1, #d, k= bitxor(k, d[i])); k; \\ _Michel Marcus_, Jul 21 2021

%Y Cf. A000040, A346408, A346511 (XOR of digits of n), A003987 (Table of n XOR m read by antidiagonals).

%K base,nonn,less

%O 1,1

%A _Jeremias M. Gomes_, Jul 21 2021