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%I #19 Feb 01 2022 00:52:27
%S 1,2,3,6,36,648,139968,3265173504,296148833645101056,
%T 135345882205792807436868315512832,
%U 130876399105969522361889021452224949874232743897657526714368
%N a(n) = a(n-1)*a(n-2)*a(n-3) with a(1)=1, a(2)=2 and a(3)=3.
%H John Cerkan, <a href="/A000308/b000308.txt">Table of n, a(n) for n = 1..15</a>
%F a(n) = 2^A001590(n-1)*3^A000073(n-1). - _Henry Bottomley_, Jul 16 2001
%e a(6)=36*6*3=648.
%p A000308 := proc(n) option remember; if n <=3 then n else A000308(n-1)*A000308(n-2)*A000308(n-3); fi; end;
%Y Cf. A000304, A000336, A063401.
%K nonn
%O 1,2
%A _N. J. A. Sloane_
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