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!)
A062030 Group even numbers into (2,4), (6,8,10,12), (14,16,18,20,22,24), ...; a(n) = product of n-th group. 5
8, 5760, 42577920, 1300252262400, 111644006842368000, 21695920874860629196800, 8291067715225260172247040000, 5644260808699395278689265516544000, 6360332664265371581768550654463180800000, 11209384544297234954537967755979151481241600000, 29531169256166572959626706182319305835700813824000000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) = 4^n * Gamma(1 + n + n^2)/Gamma(1 - n + n^2). - G. C. Greubel, May 06 2022
EXAMPLE
a(3) = 14*16*18*20*22*24 = 42577920.
MATHEMATICA
Table[4^n*Gamma[1+n+n^2]/Gamma[1-n+n^2], {n, 30}] (* G. C. Greubel, May 05 2022 *)
PROG
(PARI) { for(n=1, 100, write("b062030.txt", n, " ", 2^(2*n)*(n^2+n)!/(n^2-n)!) ) } \\ Harry J. Smith, Jul 30 2009
(SageMath) [4^n*gamma(1+n+n^2)/gamma(1-n+n^2) for n in (1..30)] # G. C. Greubel, May 05 2022
CROSSREFS
Sequence in context: A093937 A318897 A178329 * A052497 A304426 A316281
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Jun 02 2001
EXTENSIONS
More terms from Jason Earls, Jun 10 2001
Typo in a(4) corrected by N. J. A. Sloane, Aug 31 2009 using the b-file.
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 09:04 EDT 2024. Contains 371240 sequences. (Running on oeis4.)