login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A004733 Denominator of n!!/(n+3)!!. 2
3, 8, 15, 16, 105, 128, 315, 256, 3465, 1024, 9009, 2048, 45045, 32768, 109395, 65536, 2078505, 262144, 4849845, 524288, 22309287, 4194304, 50702925, 8388608, 456326325, 33554432, 1017958725, 67108864 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

REFERENCES

S. Janson, On the traveling fly problem, Graph Theory Notes of New York, Vol. XXXI, 17, 1996.

LINKS

Table of n, a(n) for n=0..27.

S. Janson, On the traveling fly problem

PROG

(PARI) a(n) = denominator(prod(i=0, floor((n-1)/2), n-2*i)/prod(i=0, floor((n+2)/2), n+3-2*i)) \\ Michel Marcus, May 24 2013

CROSSREFS

Cf. A004732.

Cf. A001801.

Sequence in context: A135872 A242245 A045263 * A310307 A051210 A191773

Adjacent sequences:  A004730 A004731 A004732 * A004734 A004735 A004736

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane.

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 26 11:58 EST 2022. Contains 350598 sequences. (Running on oeis4.)