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%I #12 Dec 06 2015 11:34:44
%S 9,8,1,0,5,7,9,7,3,0,8,7,6,1,1,4,9,7,7,3,9,6,8,0,2,8,1,4,2,0,0,0,5,0,
%T 8,2,5,7,0,4,0,9,5,2,1,0,2,9,9,5,8,4,8,5,6,3,5,0,4,2,0,2,5,9,4,0,7,4,
%U 9,2,1,4,1,8,5,4,3,8,3,5,5,0,9,4,8,8,3,8,9,9,8,5,9,7,0,0,6,9,5,9,5,1,3,4,3
%N Decimal expansion of (Pi/4)^N*(N^N/N!)^2 for N = 3.
%C The general expression is a lower bound (due to H. Minkowski) on the discriminant of a number field of degree N.
%C The corresponding value for N = 2 matches A091476.
%D B. Mazur, Algebraic Numbers, in The Princeton Companion to Mathematics, Editor T. Gowers, Princeton University Press, 2008, Section IV.1, page 330.
%H Stanislav Sykora, <a href="/A261813/b261813.txt">Table of n, a(n) for n = 1..2000</a>
%F Equals 81*Pi^3/256.
%e 9.8105797308761149773968028142000508257040952102995848563504202594...
%t n = 3; First@ RealDigits[N[(Pi/4)^n (n^n/n!)^2, 120]] (* _Michael De Vlieger_, Nov 19 2015 *)
%o (PARI) N=3;(Pi/4)^N*(N^N/N!)^2
%Y Cf. A000796, A091476 (N=2).
%K nonn,cons
%O 1,1
%A _Stanislav Sykora_, Nov 19 2015