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!)
A093908 Let f(k, n) be the product of n consecutive numbers beginning with k. Then a(n) is the least k > 1+n*(n-1)/2 such that f(k, n) is a multiple of f(1+n*(n-1)/2, n). 1

%I #7 Dec 05 2013 19:56:49

%S 2,3,8,39,52,187,204,863,773,6621,34038,2404,34440,223097,11976,

%T 1106290,1980047,85119892,15308072,496820597,2590416388,1087065675,

%U 4736428784,1128909067,242793786666,2791304683100,273924845940

%N Let f(k, n) be the product of n consecutive numbers beginning with k. Then a(n) is the least k > 1+n*(n-1)/2 such that f(k, n) is a multiple of f(1+n*(n-1)/2, n).

%C f(k, n) = A008279(n+k-1, n). 1+n*(n-1)/2 = A000124(n-1). f(1+n*(n-1)/2, n) = A057003(n).

%C a(28) > 88*10^12.

%e a(4) = 39 because 39*40*41*42 is divisible by 7*8*9*10. No

%e smaller set gives a product that is a multiple of 7*8*9*10.

%Y Cf. A000124, A008279, A057003, A093909.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Apr 24 2004

%E Edited and extended by _David Wasserman_, Apr 25 2007

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 18 16:22 EDT 2024. Contains 371780 sequences. (Running on oeis4.)