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!)
A078638 rad(n(n+1)(n+2)(n+3)). 1
6, 30, 30, 210, 210, 42, 210, 330, 330, 4290, 6006, 2730, 2730, 3570, 510, 1938, 9690, 3990, 43890, 53130, 10626, 7590, 8970, 390, 2730, 15834, 6090, 188790, 26970, 10230, 34782, 39270, 39270, 132090, 147630, 54834, 274170, 303810, 111930 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
a(3)=rad(3*4*5*6)=30.
PROG
(PARI) rad(n)=local(p, i); p=factor(n)[, 1]; prod(i=1, length(p), p[i]) for (k=1, 100, print1(rad(k*(k+1)*(k+2)*(k+3))", "))
(PARI) a(n)=my(v=[]); for(i=0, 3, v=concat(v, factor(n+i)[, 1])); v=vecsort(v, , 8); prod(i=1, #v, v[i]) \\ Charles R Greathouse IV, Jun 20 2013
CROSSREFS
Cf. A007947.
Sequence in context: A123624 A287733 A066197 * A068510 A147798 A351226
KEYWORD
nonn
AUTHOR
Jon Perry, Dec 12 2002
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 April 25 11:39 EDT 2024. Contains 371969 sequences. (Running on oeis4.)