cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A377479 Decimal expansion of the smallest positive real root of the equation cos(x) + x*sin(x) = 0.

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%I A377479 #11 Jan 23 2025 22:10:50
%S A377479 2,7,9,8,3,8,6,0,4,5,7,8,3,8,8,7,1,3,6,7,2,0,2,4,8,9,0,3,1,3,9,5,7,0,
%T A377479 6,7,0,6,3,4,6,0,8,7,9,0,7,5,4,1,0,1,0,4,3,5,9,6,4,2,1,7,1,0,5,5,6,2,
%U A377479 4,9,5,0,8,2,7,8,5,3,5,3,2,2,6,2,5,5,0,6,5,6,8,5,3,8,4,2,6,8,7,9
%N A377479 Decimal expansion of the smallest positive real root of the equation cos(x) + x*sin(x) = 0.
%C A377479 The absolute value of the x-coordinate of the tangent point between the cosine graph and the straight line through the origin.
%H A377479 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%e A377479 2.79838604578388713672024890313957...
%t A377479 ndigits=100; First[RealDigits[First[x/.NSolve[Cos[x]+x Sin[x]==0,x,ndigits]],10,ndigits]]
%t A377479 (* or *)
%t A377479 RealDigits[BesselJZero[-3/2, 1], 10, 100][[1]] (* _Vaclav Kotesovec_, Oct 31 2024 *)
%o A377479 (PARI) \\ Note: besseljzero not guaranteed to work here since -3/2 < 0.
%o A377479 solve(x=2,3, cos(x)+x*sin(x)) \\ _Charles R Greathouse IV_, Jan 23 2025
%Y A377479 Cf. A003957, A115365, A197002, A377480, A377481.
%K A377479 nonn,cons
%O A377479 1,1
%A A377479 _Stefano Spezia_, Oct 29 2024