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 A378070 #29 Dec 15 2024 05:26:59 %S A378070 1,0,1,2,9,24,100,300,1225,3920,15876,52920,213444,731808,2944656, %T A378070 10306296,41409225,147232800,590976100,2127513960,8533694884, %U A378070 31031617760,124408576656,456164781072,1828114918084,6749962774464,27043120090000,100445874620000,402335398890000 %N A378070 a(n) = binomial(n - 1, ceiling(n/2)) * binomial(n - 1, ceiling(n/2) - 1). %H A378070 Paolo Xausa, <a href="/A378070/b378070.txt">Table of n, a(n) for n = 0..1000</a> %F A378070 a(n) = binomial(n - 1, floor(n/2) - 1) * binomial(n - 1, ceiling(n/2) - 1). %p A378070 a := n -> binomial(n-1, floor((n+1)/2))*binomial(n-1, floor((n+1)/2)-1); %p A378070 seq(a(n), n = 0..27); %t A378070 A378070[n_] := Binomial[n - 1, #]*Binomial[n - 1, # - 1] & [Ceiling[n/2]]; %t A378070 Array[A378070, 30, 0] (* _Paolo Xausa_, Dec 14 2024 *) %Y A378070 Cf. A007318, A060150 (even bisection), A135389 (odd bisection), A378060. %K A378070 nonn,easy %O A378070 0,4 %A A378070 _Peter Luschny_, Dec 13 2024