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%I #11 Jul 04 2013 03:24:32
%S 1,2,6,60,420,4620,60060,4084080,232792560,5354228880,155272637520,
%T 4813451763120,178097715235440,7302006324653040,313986271960080720,
%U 14757354782123793840,782139803452561073520,46146248403701103337680,2814921152625767303598480
%N a(0)=1 and a(n)=prime(n)*lcm(prime(n)-1, a(n-1)) for n > 0.
%C A226957(a(n)) = n.
%C Is this a subset of A168264? - _Ralf Stephan_, Jul 04 2013
%H Charles R Greathouse IV, <a href="/A226959/b226959.txt">Table of n, a(n) for n = 0..347</a>
%t a[0]=1; a[n_]:= a[n]=Prime[n]*LCM[a[n - 1],Prime[n] -1];
%t Table[a[i], {i, 1, 18}]
%o (PARI) a(n)=if(n,my(v=primes(n),e=vector(n,i,1),f,j); forprime(p=2,v[n], f=factor(p-1); for(i=1,#f~,if(f[i,2]>1,j=primepi(f[i,1]);e[j]=max(e[j],f[i,2])))); prod(i=1,n,v[i]^e[i]),1) \\ _Charles R Greathouse IV_, Jun 28 2013
%Y Cf. A226957, A002110.
%K nonn
%O 0,2
%A _José María Grau Ribas_, Jun 24 2013