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%I #21 Sep 08 2022 08:45:54
%S 4,3,3,4,5,2,3,4,5,3,4,2,3,4,5,3,5,2,4,5,2,4,5,3,2,3,4,5,2,3,4,5,3,4,
%T 3,4,2,4,5,3,5,2,5,2,3,4,4,4,5,2,3,5,2,5,3,5,3,4,2,3,4,3,4,5,2,3,4,2,
%U 5,2,3,5,4,2,4,5,3,2,3,2,5,2,5,2,4,5,3,2,3,4,5,5,4,5,4,5,3,3,4,2,4,3
%N a(n) = (n-th prime modulo 3) + (n-th prime modulo 4).
%C a(n) = 2 iff prime(n) == 1 (mod 12); a(n) = 2 for prime(n) = 13, 37, 61, 73, 97, 109, ... (A068228).
%C a(n) = 5 iff prime(n) == 11 (mod 12); a(n) = 5 for prime(n) = 11, 23, 47, 59, 71, 83, ... (A068231).
%C For n > 2, a(n) = 3 iff prime(n) == 5 (mod 12); a(n) = 3 for prime(n) = 5, 17, 29, 41, 53, 89, ... (A040117).
%C For n > 2, a(n) = 4 iff prime(n) == 7 (mod 12); a(n) = 4 for prime(n) = 7, 19, 31, 43, 67, 79, ... (A068229).
%t Mod[#,3]+Mod[#,4]&/@Prime[Range[110]] (* _Harvey P. Dale_, Nov 09 2011 *)
%o (Magma) A180217:=func< n | p mod 3 + p mod 4 where p is NthPrime(n) >; [ A180217(n): n in [1..105] ]; // _Klaus Brockhaus_, Jan 18 2011
%Y Equals A039701 + A039702.
%Y Cf. A068228, A068231, A040117, A068229, A039710.
%K nonn
%O 1,1
%A _Zak Seidov_, Jan 16 2011
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