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%I #9 Nov 26 2018 17:13:40
%S 1,1,2,6,2,24,2,10,6,24,2,144,2,24,24,14,2,144,2,144,24,24,2,240,6,24,
%T 10,144,2,80,2,22,24,24,24,54,2,24,24,240,2,80,2,144,144,24,2,336,6,
%U 144,24,144,2,240,24,240,24,24,2,1728,2,24,144,26,24,80,2,144,24,80,2,360,2,24,144,144,24,80,2,336,14,24,2,1728
%N a(1) = a(2) = 1; for n > 2, a(n) = A181819(n) * a(A181819(n)).
%H Antti Karttunen, <a href="/A320118/b320118.txt">Table of n, a(n) for n = 1..10080</a>
%F a(1) = a(2) = 1; for n > 2, a(n) = A181819(n) * a(A181819(n)).
%t Nest[Append[#1, #2 #1[[#2]] ] & @@ {#, Times @@ Prime@ FactorInteger[Length@ # + 1][[All, -1]]} &, {1, 1}, 82] (* _Michael De Vlieger_, Nov 25 2018 *)
%o (PARI)
%o A181819(n) = factorback(apply(e->prime(e),(factor(n)[,2])));
%o A320118(n) = if(n<=2,1,A181819(n)*A320118(A181819(n)));
%Y Cf. A181819, A182850.
%Y Cf. also A304465, A320016.
%K nonn
%O 1,3
%A _Antti Karttunen_, Nov 24 2018