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a(1)=1; for n > 0, a(n+1) = rad(a(n))*n where rad=A007947.
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%I #40 Jun 12 2022 06:42:19

%S 1,1,2,6,24,30,180,210,1680,1890,2100,2310,27720,30030,420420,450450,

%T 480480,510510,9189180,9699690,193993800,203693490,213393180,

%U 223092870,5354228880,5577321750,5800414620,6023507490,6246600360,6469693230,194090796900,200560490130

%N a(1)=1; for n > 0, a(n+1) = rad(a(n))*n where rad=A007947.

%F a(1)=1; for n > 1, a(n) = (n-1) * Product_{p prime < (n-1)} p. - _Pedro Caceres_, Mar 12 2018

%F a(A008864(n)) = A002110(n). - _Michel Marcus_, Mar 17 2018

%t rad[n_] := Times @@ (First@# & /@ FactorInteger@n); a[n_] := (n -1)rad[a[n -1]]; a[1] = 1; Array[a, 30] (* _Robert G. Wilson v_, Dec 14 2016 and modified Dec 24 2016 *)

%o (PARI) a(n) = if(n==1, 1, (n-1)*prod(k=1, primepi(n-2), prime(k))); \\ _Daniel Suteu_, Dec 14 2016

%o (PARI) rad(n) = factorback(factorint(n)[, 1]);

%o a(n) = if (n==1, 1, (n-1)*rad(a(n-1))); \\ _Michel Marcus_, Dec 21 2016

%Y Cf. A002110, A008864, A049614.

%K nonn

%O 1,3

%A _Reinhard Zumkeller_, Jan 05 2002

%E More terms from _Michel Marcus_, Mar 17 2018