A298742 - OEIS

%I #20 Sep 08 2022 08:46:20

%S 2,1,3,2,2,4,1,8,8,2,3,1,1,9,0,0,1,9,5,6,5,5,0,7,2,3,3,8,1,5,7,3,0,0,

%T 6,5,7,0,8,4,7,8,6,1,8,6,0,9,5,8,3,2,9,8,4,1,4,2,1,7,7,7,5,4,1,6,5,9,

%U 9,4,3,3,7,4,2,5,9,5,9,6,2,5,8,3,9,2

%N Decimal expansion of (1/2)(1 + sqrt(5 + 4*sqrt(2))).

%C Positive zero of x^2 - x - 1 - sqrt(2).

%H Clark Kimberling, <a href="/A298742/b298742.txt">Table of n, a(n) for n = 1..10000</a>

%e 2.1322418823119001957...

%t r = (1/2)*(1 + Sqrt[5 + 4*Sqrt[2]])

%t RealDigits[N[r, 100], 10][[1]];  (* A298742 *)

%o (PARI) (1/2)*(1 + sqrt(5 + 4*sqrt(2))) \\ _Altug Alkan_, Apr 12 2018

%o (Magma) SetDefaultRealField(RealField(100)); (1/2)*(1 + Sqrt(5 + 4*Sqrt(2))); // _G. C. Greubel_, Aug 20 2018

%Y Cf. A190179, A298740.

%K nonn,easy,cons

%O 1,1

%A _Clark Kimberling_, Feb 13 2018