%I #11 Apr 03 2020 11:20:44
%S 3,1,4,1,5,9,2,6,5,1,8,3,2,9,0,0,5,6,2,8,7,8,6,7,4,4,8,2,8,8,3,4,3,3,
%T 3,7,1,6,7,7,5,1,1,5,3,3,4,0,2,8,2,2,3,0,8,4,5,8,1,0,7,6,3,3,2,8,5,5,
%U 1,0,7,3,1,3,8,4,0,9,6,5,9,5,4,9,4,3,7,6,1,4,8,7,4,9,9,1,2,1,9,6
%N Decimal expansion of (sqrt(20467) - sqrt(19578) + sqrt(10177) - sqrt(9553))/2.
%C This is the best approximation to Pi using four square roots (with coefficients +/-1) of n < 200000, see also A087477.
%e 3.14159265183290...
%t RealDigits[N[(Sqrt[20467] - Sqrt[19578] + Sqrt[10177] - Sqrt[9553])/2, 101]] (* _Georg Fischer_, Apr 03 2020 *)
%Y Cf. A000796, A087477.
%K easy,nonn,cons
%O 1,1
%A _Zak Seidov_, Sep 09 2003
%E a(100) corrected by _Georg Fischer_, Apr 03 2020