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%I #9 Sep 20 2022 07:52:35
%S 1,2,9,52,738,2829,53643,162438,4023888,166236537,921787428,
%T 48034254669,935251837851,2558696229078,68055676507664,
%U 2655011771373417,210067141980993186,831463105466530077,42882922858578320598
%N Binary encoding of quadratic residue set for each prime. a(n) = A055094(A000040(n)).
%F a(A080148(n)) = A080117(A080148(n)).
%p with(numtheory,ithprime); A080146 := n -> A055094(ithprime(n));
%t A055094[n_] := With[{rr = Table[Mod[k^2, n], {k, 1, n-1}] // Union}, Boole[MemberQ[rr, #]]& /@ Range[n-1]] // FromDigits[#, 2]&;
%t a[n_] := A055094[Prime[n]];
%t Table[a[n], {n, 1, 20}] (* _Jean-François Alcover_, Sep 20 2022 *)
%o (PARI) a(n) = my(p=prime(n)); sum(k=1, p-1, 2^(k-1)*(0<sum(i=1, p-1, i^2%p==p-k))); \\ _Michel Marcus_, Sep 20 2022; after A055094
%Y Cf. A000040, A055094, A080117, A080148.
%K nonn
%O 1,2
%A _Antti Karttunen_, Feb 11 2003