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a(n) = prime(n)^2 mod prime(n-2).
1

%I #15 Jan 06 2019 04:54:33

%S 1,1,1,1,3,10,2,5,18,6,7,36,36,14,3,11,5,39,36,64,27,21,30,55,36,36,

%T 36,36,106,98,100,64,7,5,64,144,100,100,144,64,144,144,36,36,196,178,

%U 45,36,36,100,64,144,15,144,144,64,64,100,36,144,10,31,36,36,11,83,256,144,36,100,196,196,144,100,100,196

%N a(n) = prime(n)^2 mod prime(n-2).

%H Harvey P. Dale, <a href="/A179397/b179397.txt">Table of n, a(n) for n = 3..1000</a>

%e a(1) = 5^2 mod 2 = 25 mod 2 = 1;

%e a(2) = 7^2 mod 3 = 49 mod 3 = 1;

%e a(3) = 11^2 mod 5 = 121 mod 5 = 1;

%e a(4) = 13^2 mod 7 = 169 mod 7 = 1;

%e a(5) = 17^2 mod 11 = 289 mod 11 = 3.

%p A179397 := proc(n) ithprime(n)^2 mod ithprime(n-2); end proc: # _R. J. Mathar_, Jan 09 2011

%t PowerMod[#[[3]],2,#[[1]]]&/@Partition[Prime[Range[80]],3,1] (* _Harvey P. Dale_, Oct 21 2018 *)

%Y Cf. A038702.

%K nonn

%O 3,5

%A _Umut Uludag_, Jan 07 2011