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A010465 Decimal expansion of square root of 7.

%I A010465 #45 Mar 14 2025 17:11:24
%S A010465 2,6,4,5,7,5,1,3,1,1,0,6,4,5,9,0,5,9,0,5,0,1,6,1,5,7,5,3,6,3,9,2,6,0,
%T A010465 4,2,5,7,1,0,2,5,9,1,8,3,0,8,2,4,5,0,1,8,0,3,6,8,3,3,4,4,5,9,2,0,1,0,
%U A010465 6,8,8,2,3,2,3,0,2,8,3,6,2,7,7,6,0,3,9,2,8,8,6,4,7,4,5,4,3,6,1
%N A010465 Decimal expansion of square root of 7.
%C A010465 Continued fraction expansion is 2 followed by {1, 1, 1, 4} repeated. - _Harry J. Smith_, Jun 01 2009
%C A010465 The convergents to sqrt(7) are given in A041008/A041009. - _Wolfdieter Lang_, Nov 22 2017
%H A010465 Harry J. Smith, <a href="/A010465/b010465.txt">Table of n, a(n) for n = 1..20000</a>
%H A010465 Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/sqrt_base">Index of expansions of sqrt(d) in base b</a>.
%H A010465 R. J. Nemiroff & J. Bonnell, <a href="http://antwrp.gsfc.nasa.gov/htmltest/gifcity/sqrt7.1mil">The first 1 million digits of the square root of 7</a>.
%H A010465 Simon Plouffe, Plouffe's Inverter, <a href="http://www.plouffe.fr/simon/constants/sqrt7.txt">sqrt(7) to 100000 digits</a>.
%H A010465 <a href="/index/Al#algebraic_02">Index entries for algebraic numbers, degree 2</a>.
%F A010465 Equals 8*cos(Pi/14)*sin(2*Pi/14)*cos(3*Pi/14). - _Gerry Martens_, Mar 13 2025
%e A010465 2.645751311064590590501615753639260425710259183082450180368334459201...
%t A010465 RealDigits[N[Sqrt[7], 200]][[1]] (* _Vladimir Joseph Stephan Orlovsky_, Feb 21 2011 *)
%o A010465 (PARI)  default(realprecision, 20080); x=sqrt(7); for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b010465.txt", n, " ", d));  \\ _Harry J. Smith_, Jun 01 2009
%o A010465 (Magma) SetDefaultRealField(RealField(100)); Sqrt(7); // _Vincenzo Librandi_, Feb 15 2020
%Y A010465 Cf. A010121 (continued fraction), A041008/A041009.
%K A010465 nonn,cons,easy
%O A010465 1,1
%A A010465 _N. J. A. Sloane_