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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.

A245771 Decimal expansion of 'b', an optimal stopping constant associated with the secretary problem when the objective is to maximize the hiree's expected quality.

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%I A245771 #40 Jun 10 2025 01:12:48
%S A245771 1,7,6,7,9,9,3,7,8,6,1,3,6,1,5,4,0,5,0,4,4,3,6,3,4,4,0,6,7,8,1,1,3,2,
%T A245771 3,3,1,0,7,7,6,8,1,4,3,3,1,3,1,9,5,6,5,1,5,5,7,6,9,8,6,0,5,9,6,2,6,0,
%U A245771 0,0,7,6,4,6,0,6,3,8,7,5,1,4,4,4,4,8,1,6,5,1,6,3,2,5,6,8,2,5,0
%N A245771 Decimal expansion of 'b', an optimal stopping constant associated with the secretary problem when the objective is to maximize the hiree's expected quality.
%D A245771 Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 5.15, p. 362.
%H A245771 Steven Finch, <a href="https://arxiv.org/abs/2409.03510">A Deceptively Simple Quadratic Recurrence</a>, arXiv:2409.03510 [math.NT], 2024.
%H A245771 Steven Finch, <a href="https://arxiv.org/abs/2411.16062">Exercises in Iterational Asymptotics</a>, arXiv:2411.16062 [math.NT], 2024. See p. 9.
%H A245771 Steven Finch, <a href="https://arxiv.org/abs/2506.07625">Half-Iterates of x(1+x), sin(x) and exp(x/e)</a>, arXiv:2506.07625 [math.NT], 2025. See p. 4.
%H A245771 Jon E. Schoenfield, <a href="/A245771/a245771.txt">Magma program</a> communicated to J.-F. Alcover.
%H A245771 Eric Weisstein's MathWorld, <a href="https://mathworld.wolfram.com/SultansDowryProblem.html">Sultan's Dowry Problem</a>.
%H A245771 Wikipedia, <a href="http://en.wikipedia.org/wiki/Secretary_problem">Secretary problem</a>.
%F A245771 Q(0) = 0, Q(n) = (1/2)*(1+Q(n-1)^2), Q(n) ~ 1-2/(n+log(n)+b) when n -> infinity.
%e A245771 1.767993786136154050443634406781132331077681433131956515576986059626...
%t A245771 nmax = 10^10; dn = 10^6; db = 2*10^-16; b0 = p = 3; q = 10/3; b = q - Log[2]; f = Compile[{n, p, q}, (p*((p-5)*p + 8) + n*(n*p + (2*p-5)*p + 2) + q - 5)/((p-5)*p + n*(n + 2*p - 5) + 7)]; For[n = 3, n <= nmax, n++, If[Divisible[n, dn], b0 = b]; r = f[n, p, q]; b = r - Log[n]; p = q; q = r; If[Divisible[n, dn], Print["n = ", n, " b = ", b]; If[Abs[b - b0] < db, Break[]]]]; RealDigits[b] // First
%o A245771 (Magma) // See the link to _Jon E. Schoenfield_'s program.
%Y A245771 Cf. A054404, A242672, A242673, A242674, A243533.
%K A245771 nonn,cons
%O A245771 1,2
%A A245771 _Jean-François Alcover_, Aug 01 2014
%E A245771 Extended to 99 digits using _Jon E. Schoenfield_'s evaluation, Sep 05 2016