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A334143 a(n) = bitwise NOR of prime(n) and prime(n+1).

%I A334143 #31 Oct 13 2023 11:29:12
%S A334143 0,0,0,0,0,2,12,8,0,0,0,18,20,16,0,0,0,0,56,48,48,32,36,6,26,24,16,16,
%T A334143 2,0,0,116,116,96,104,96,64,88,80,64,72,64,0,58,56,40,32,0,24,18,16,0,
%U A334143 4,4,248,240,240,224,226,228,192,200,200,192,194,128,164
%N A334143 a(n) = bitwise NOR of prime(n) and prime(n+1).
%H A334143 Rémy Sigrist, <a href="/A334143/b334143.txt">Table of n, a(n) for n = 1..10000</a>
%H A334143 Wikipedia, <a href="https://en.wikipedia.org/wiki/Bitwise operation">Bitwise operation</a>
%F A334143 a(n) = A035327(A175329(n)).
%e A334143 a(6) = prime(6) NOR prime(7) = 13 NOR 17 = 2.
%p A334143 a:= n-> Bits[Nor](ithprime(n), ithprime(n+1)):
%p A334143 seq(a(n), n=1..70);  # _Alois P. Heinz_, Apr 15 2020
%t A334143 A334143[n_]:=With[{b=BitOr[Prime[n],Prime[n+1]]},2^BitLength[b]-b-1];Array[A334143,100] (* _Paolo Xausa_, Oct 13 2023 *)
%o A334143 (Python)
%o A334143 def NORprime(n):
%o A334143     s = str(bin(primes[n]))[2:]
%o A334143     t = str(bin(primes[n-1]))[2:]
%o A334143     k = (len(s) -  len(t))
%o A334143     t = k*'0' + t
%o A334143     r = ''
%o A334143     for i in range(len(s)):
%o A334143         if s[i] == t[i] and s[i] == '0':
%o A334143             r += '1'
%o A334143         else:
%o A334143             r += '0'
%o A334143     return int(r,2)
%o A334143 (PARI) a(n) = my(x=bitor(prime(n), prime(n+1))); bitneg(x, #binary(x)); \\ _Michel Marcus_, Apr 16 2020
%Y A334143 Cf. A000040, A112591, A145382, A175330.
%K A334143 nonn,base
%O A334143 1,6
%A A334143 _Christoph Schreier_, Apr 15 2020