cp's OEIS Frontend

A244354 Decimal expansion of 'mu', a Sobolev isoperimetric constant related to the "membrane inequality", arising from the study of a vibrating membrane that is stretched across the unit disk and fastened at its boundary.

%I A244354 #15 Feb 16 2025 08:33:23
%S A244354 1,7,2,9,1,5,0,6,9,0,3,0,6,4,4,9,2,6,9,1,8,8,6,6,8,3,4,4,3,0,1,0,3,7,
%T A244354 1,4,9,0,2,0,0,6,7,1,1,5,9,2,8,3,9,2,2,5,6,4,6,0,6,8,0,8,4,8,2,9,4,8,
%U A244354 1,0,6,3,1,6,3,1,5,6,3,9,9,8,8,7,3,2,4,4,0,0,9,0,1,8,3,5,8,9,5,1,8,2,2,5
%N A244354 Decimal expansion of 'mu', a Sobolev isoperimetric constant related to the "membrane inequality", arising from the study of a vibrating membrane that is stretched across the unit disk and fastened at its boundary.
%D A244354 Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 3.6 Sobolev Isoperimetric Constants,  p. 221.
%H A244354 Eric Weisstein's MathWorld, <a href="https://mathworld.wolfram.com/BesselFunctionZeros.html">Bessel Function Zeros</a>
%H A244354 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%F A244354 mu = 1/theta^2, where theta is A115368, the first positive zero of the Bessel function J0(x).
%e A244354 0.17291506903064492691886683443...
%t A244354 theta = BesselJZero[0, 1]; mu = 1/theta^2; RealDigits[mu, 10, 104] // First
%o A244354 (PARI) 1/besseljzero(0)^2 \\ _Charles R Greathouse IV_, Aug 23 2022
%Y A244354 Cf. A115368.
%K A244354 nonn,cons,easy
%O A244354 0,2
%A A244354 _Jean-François Alcover_, Jun 26 2014