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Least integer having Radon random number n.
(Formerly M0723 N0270)
1

%I M0723 N0270 #35 Sep 08 2022 08:44:31

%S 1,2,3,5,10,18,35,63,126,231,462,858,1716,3218,6435,12155,24310,46189,

%T 92378,176358,352716,676039,1352078,2600150,5200300,10029150,20058300,

%U 38779380,77558760,150270098,300540195,583401555,1166803110,2268783825,4537567650

%N Least integer having Radon random number n.

%C Old name was "From Radon's theorem".

%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H Matthew House, <a href="/A002661/b002661.txt">Table of n, a(n) for n = 1..3328</a>

%H J. Eckhoff, <a href="http://www.digizeitschriften.de/dms/img/?PID=GDZPPN002476398">Der Satz von Radon in konvexen Produktstrukturen II</a>, Monat. f. Math., 73 (1969), 7-30.

%H Michael Hendriksen and Nils Kapust, <a href="https://doi.org/10.1007/s11538-021-00911-6">On the Comparison of Incompatibility of Split Systems Across Different Numbers of Taxa</a>, Bull. of Math. Biology (2021) Vol. 83, Art. No. 78.

%F a(n) = ceiling(binomial(n + 1, floor((n + 1) / 2)) / 2). - _Sean A. Irvine_, May 21 2014; corrected by _Matthew House_, Jul 29 2015

%t Table[Ceiling[Binomial[n + 1, Floor[(n + 1)/2]]/2], {n, 40}] (* _Vincenzo Librandi_, Jul 30 2015 *)

%o (Magma) [Ceiling(Binomial(n+1, Floor((n+1)/2))/2): n in [1..40]]; // _Vincenzo Librandi_, Jul 30 2015

%o (PARI) vector(40, n, ceil(binomial(n + 1, floor((n + 1) / 2)) / 2)) \\ _Michel Marcus_, Jul 30 2015

%K nonn

%O 1,2

%A _N. J. A. Sloane_

%E New name and more terms from _Sean A. Irvine_, May 21 2014