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%I #38 Dec 21 2023 15:12:02
%S 2,1,0,1,2,1,1,2,1,4,2,1,2,1,3,1,2,2,1,2,1,2,1,4,1,4,1,3,2,3,1,2,1,6,
%T 2,6,1,1,1,1,2,4,2,1,1,18,10,1,1,4,9,2,2,2,1,3,2,2,1,10,1,1,7,2,1,1,6,
%U 1,3,4,3,2,1,1,2,1,2,1,4,2,2,10,2,1,2,1
%N a(n) = 2*(p_n - 1)/A060305(n) iff p_n == +/- 1 (mod 5), 2*(p_n + 1)/A060305(n) iff p_n == +/- 2 (mod 5), 0 iff p_n = 5.
%F a(n) == 0 (mod 2) for prime(n) == +/- 1 (mod 5) and n > 2.
%F a(n) == 1 (mod 2) for Prime(n) == +/- 2 (mod 5) and n > 2.
%F a(n) = 1 iff prime(n) in A071774.
%F a(n) = 2 iff prime(n) in ({2} union A003147)/{5}.
%F a(n) = 3 iff prime(n) in A308784.
%F a(n) = 4 iff prime(n) in A308787.
%F a(n) = 6 iff prime(n) in A308788.
%F a(n) = 7 iff prime(n) in A308785.
%F a(n) = 8 iff prime(n) in A308789.
%F a(n) = 9 iff prime(n) in A308786.
%F a(n) = 10 iff prime(n) in A308790.
%F a(n) = 12 iff prime(n) in A308791.
%F a(n) = 14 iff prime(n) in A308792.
%F a(n) = 16 iff prime(n) in A308793.
%F a(n) = 18 iff prime(n) in A308794.
%F a(n) = A296240(n) iff prime(n) == +/- 2 (mod 5) and n > 3.
%F a(n) = 2*A296240(n) iff prime(n) == +/- 1 (mod 5) and n > 3.
%F a(n) in {2^k: k > 1} iff prime(n) in {A047650}.
%F a(n) == 3 (mod 6) iff prime(n) in {A124096}.
%F a(n) == 6 (mod 12) iff prime(n) in {A046652}.
%F a(n) == 0 (mod 14) iff prime(n) in {A125252}.
%Y Cf. A000040, A003147, A060305, A047650, A047652, A071774, A124096, A124253, A296240, A308784 - A308794.
%K nonn
%O 1,1
%A _A.H.M. Smeets_, Oct 29 2023
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