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.
%I A307131 #17 Jun 28 2019 08:58:55
%S A307131 1,2,5,4,37,52,349,338,11873,14554,157567,466498,11994551,41582906,
%T A307131 618626159,614191052,7545655031,92853583996,1755370057489,
%U A307131 8737266957604,365468962351379,2002633668589496,45904893141293831
%N A307131 Numerator of the expected fraction of occupied places on n-length lattice randomly filled with 2-length segments.
%C A307131 The limit of expected fraction of occupied places on n-length lattice randomly filled with 2-length segments at n tends to infinity is equal to 1-1/e^2 (see A219863).
%H A307131 D. G. Radcliffe, <a href="https://mathblag.files.wordpress.com/2012/12/fatmen.pdf">Fat men sitting at a bar</a>
%F A307131 Numerator of f(n), where f(0)=0; f(1)=0 and f(n) = (2 + 2(n-2)f(n-2) + (n-1)(n-2)f(n-1))/(n(n-1)) for n>1.
%e A307131 0, 1, 2/3, 5/6, 4/5, 37/45, 52/63, 349/420, 338/405, 11873/14175, ...
%t A307131 RecurrenceTable[{f[n] == (2 + 2 (n - 2) f[n - 2] + (n - 1) (n - 2) f[n - 1])/(n (n - 1)),f[0] == 0, f[1] == 0}, f, {n, 2, 100}] // Numerator
%Y A307131 Cf. A219863, A231580, A307132 (denominators).
%K A307131 nonn,frac
%O A307131 1,2
%A A307131 _Philipp O. Tsvetkov_, Mar 26 2019