A088304 - OEIS

%I #9 Nov 18 2020 17:37:53

%S 1,1,1,4,4,24,24,3,27,270,270,3240,3240,45360,3024,189,189,3402,3402,

%T 68040,3240,71280,71280,2970,74250,1930500,71500,2002000,2002000,

%U 60060000,60060000,1876875,56875,1933750,55250,1989000,1989000,75582000

%N a(1) = 1. For n > 1, a(n) = a(n-1) if n is prime, a(n) = a(n-1)/n if n is composite and divides a(n-1) else a(n) = n*a(n-1).

%H Harvey P. Dale, <a href="/A088304/b088304.txt">Table of n, a(n) for n = 1..1000</a>

%t nxt[{n_,a_}]:={n+1,Which[PrimeQ[n+1],a,CompositeQ[n+1]&&Divisible[ a,n+1],a/(n+1),True,a(n+1)]}; NestList[nxt,{1,1},40][[All,2]] (* _Harvey P. Dale_, Nov 18 2020 *)

%o (PARI) b=1; for(n=2,39,if(isprime(n),a=b,if(b%n==0,a=b/n,a=n*b)); print1(b,","); b=a)

%K nonn

%O 1,4

%A _Amarnath Murthy_, Oct 01 2003

%E Extended by _Klaus Brockhaus_ and _Ray Chandler_, Oct 06 2003