login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A002661 Least integer having Radon random number n.
(Formerly M0723 N0270)
1
1, 2, 3, 5, 10, 18, 35, 63, 126, 231, 462, 858, 1716, 3218, 6435, 12155, 24310, 46189, 92378, 176358, 352716, 676039, 1352078, 2600150, 5200300, 10029150, 20058300, 38779380, 77558760, 150270098, 300540195, 583401555, 1166803110, 2268783825, 4537567650 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Old name was "From Radon's theorem".

REFERENCES

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

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

LINKS

Matthew House, Table of n, a(n) for n = 1..3328

J. Eckhoff, Der Satz von Radon in konvexen Produktstrukturen II, Monat. f. Math., 73 (1969), 7-30.

FORMULA

a(n) = ceiling(binomial(n + 1, floor((n + 1) / 2)) / 2). - Sean A. Irvine, May 21 2014; corrected by Matthew House, Jul 29 2015

MATHEMATICA

Table[Ceiling[Binomial[n + 1, Floor[(n + 1)/2]]/2], {n, 40}] (* Vincenzo Librandi, Jul 30 2015 *)

PROG

(MAGMA) [Ceiling(Binomial(n+1, Floor((n+1)/2))/2): n in [1..40]]; // Vincenzo Librandi, Jul 30 2015

(PARI) vector(40, n, ceil(binomial(n + 1, floor((n + 1) / 2)) / 2)) \\ Michel Marcus, Jul 30 2015

CROSSREFS

Sequence in context: A199594 A081172 A030032 * A216959 A065053 A237250

Adjacent sequences:  A002658 A002659 A002660 * A002662 A002663 A002664

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

New name and more terms from Sean A. Irvine, May 21 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified December 15 18:26 EST 2017. Contains 296047 sequences.