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%I #21 Dec 26 2017 12:41:16
%S 4,1,1,13,1,19,1,25,9,1,9,43,1,49,9,9,1,9,73,1,9,85,9,109,103,1,109,1,
%T 115,49,133,9,1,25,1,9,9,169,9,9,1,25,1,199,1,241,253,229,1,235,9,1,
%U 25,9,9,9,1,9,283,1,25,49,313,1,319,49,9,25,1,355,9,379
%N Prime(n)^2 mod (prime(n) + prime(n+1)).
%C a(n) = 1 if and only if prime(n) and prime(n+1) are twin prime pair (that is, prime(n+1) = 2 + prime(n)).
%t Table[Mod[Prime[n]^2, Prime[n] + Prime[n + 1]], {n, 200}]
%t PowerMod[#[[1]],2,Total[#]]&/@Partition[Prime[Range[80]],2,1] (* _Harvey P. Dale_, Dec 26 2017 *)
%o (PARI) for(n=1,200,print1(prime(n)^2%(prime(n)+prime(n+1))","))
%Y Cf. A029707, A167770.
%K nonn
%O 1,1
%A _Zak Seidov_, Sep 18 2013
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