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Decimal expansion of metallic ratio for N = 14.
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%I #20 Jul 04 2023 03:31:54

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

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

%U 6,6,2,3,9,2,3,1,0,5,3,5,1,9,4,2,5,1,9

%N Decimal expansion of metallic ratio for N = 14.

%C Decimal expansion of continued fraction [14; 14, 14, 14, ...].

%C Also largest solution of x^2 - 14 x - 1 = 0.

%C Essentially the same digit sequence as A010503, A157214, A174968 and A268683.

%C The metallic ratio's for N = A077444(n) are equal to powers of the silver ratio, i.e., A014166^(2n-1); this constant represents the special case for N = A077444(2).

%H Michael Penn, <a href="https://www.youtube.com/watch?v=4u5-phZHo60">7+5√2 is a perfect cube??</a>, YouTube video, 2022.

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Metallic_mean">Metallic mean</a>.

%F Equals 2 + 5*A014176.

%F Equals A014176^3.

%F Equals exp(arcsinh(7)). - _Amiram Eldar_, Jul 04 2023

%e 14.0710678118654752440084436210484903928483593...

%t RealDigits[7 + 5*Sqrt[2], 10, 100][[1]] (* _Amiram Eldar_, Feb 24 2022 *)

%o (PARI) (1+sqrt(2))^3

%Y Cf. A010503, A077444, A157214, A174968, A268683.

%Y Metallic ratios: A001622 (N=1), A014176 (N=2), A098316 (N=3), A098317 (N=4), A098318 (N=5), A176398 (N=6), A176439 (N=7), A176458 (N=8), A176522 (N=9), A176537 (N=10), A244593 (N=11).

%K nonn,cons

%O 2,2

%A _A.H.M. Smeets_, Feb 24 2022