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!)
A084715 Smallest number of the form n*k + 1 that is divisible by all the phi(n) numbers less than n and relatively prime to n. 0
3, 4, 9, 36, 25, 120, 105, 280, 441, 2520, 385, 277200, 70785, 56056, 585585, 5045040, 1446445, 183783600, 8729721, 40646320, 1322685, 4655851200, 37182145, 1070845776, 900951975, 5949143200, 6453758025, 80313433200, 215656441 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
LINKS
EXAMPLE
a(9) = 280= 31*9 +1 is divisible by 1,2,4,5,7 and 8.
PROG
(PARI) for (i = 2, 50, g = 1; for (j = 2, i - 1, if (gcd(i, j) == 1, g = lcm(g, j))); print1(lift(chinese(Mod(1, i), Mod(0, g))), ", ")); \\ David Wasserman, Jan 03 2005
CROSSREFS
Cf. A038610.
Sequence in context: A362353 A080849 A058857 * A225467 A225473 A015240
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Jun 11 2003
EXTENSIONS
More terms from David Wasserman, Jan 03 2005
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 29 00:26 EDT 2024. Contains 371264 sequences. (Running on oeis4.)