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Cotangent of Pi/prime(n), rounded to nearest integer.
0

%I #16 Aug 21 2024 01:55:59

%S 0,1,1,2,3,4,5,6,7,9,10,12,13,14,15,17,19,19,21,23,23,25,26,28,31,32,

%T 33,34,35,36,40,42,44,44,47,48,50,52,53,55,57,58,61,61,63,63,67,71,72,

%U 73,74,76,77,80,82,84,86,86,88,89,90,93,98,99,100,101,105,107,110,111,112

%N Cotangent of Pi/prime(n), rounded to nearest integer.

%F a(n) = round(cotan(Pi/prime(n))) or a(n) = round(1/tan(Pi/prime(n))).

%e For n=8: prime(8)=19; cotan(Pi/19) = 5.9926... => 6.

%t Table[Round[Cot[Pi/Prime[n]]], {n, 71}] (* _Jayanta Basu_, Jul 01 2013 *)

%o (PARI) a(n)=if(n>1,round(1/tan(Pi/prime(n))),0) \\ _Charles R Greathouse IV_, Jul 01 2013

%K nonn,easy

%O 1,4

%A _Werner D. Sand_, Aug 31 2002