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%I #16 Sep 08 2022 08:46:13
%S 1,2,3,3,8,10,12,12,14,12,12,10,12,16,14,14,12,12,12,12,16,18,18,14,
%T 10,8,10,20,22,24,12,18,14,18,14,16,16,16,14,18,14,16,8,18,26,28,18,
%U 10,12,12,18,18,22,18,14,14,12,12,16,26,28,20,10,20,24,30,18,16,12
%N a(n) = prime(n+3) mod prime(n).
%H Harvey P. Dale, <a href="/A261469/b261469.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = prime(n+3) mod prime(n).
%e a(3) = 13 mod 5 = 3.
%t a[n_]:=PowerMod[Prime[n + 3], 1, Prime[n]]; Table[a[n], {n, 80}] (* _Vincenzo Librandi_, Aug 20 2015 *)
%t Mod[Last[#],First[#]]&/@Partition[Prime[Range[80]],4,1] (* _Harvey P. Dale_, Jun 23 2017 *)
%o (PARI) first(m)=vector(m,i,prime(i+3)%prime(i)) \\ _Anders Hellström_, Aug 20 2015
%o (Magma) [NthPrime(n+3) mod NthPrime(n): n in [1.. 70]]; // _Vincenzo Librandi_, Aug 20 2015
%Y Cf. A031165.
%K nonn,easy,less
%O 1,2
%A _Altug Alkan_, Aug 20 2015