%I #8 Aug 13 2024 19:33:04
%S 1,1,1,1,1,2,3,8,15,48,210,1152,3780,19200,62370,322560,2162160,
%T 17418240,81081000,567705600,2481078600,16907304960,146659312800,
%U 1504935936000,8799558768000,76435881984000,819678899239200
%N a(n) = (n-c_1)(n-c_2)...(n-c_k) where c_k is the k-th composite number and is also the largest composite number < n.
%H Harvey P. Dale, <a href="/A080498/b080498.txt">Table of n, a(n) for n = 1..539</a>
%e a(6) = (6-4) = 2. a(10) = (10-4)(10-6)(10-8)(10-9) = 48.
%t Module[{nn=30,cmps},cmps=Select[Range[nn],CompositeQ];Table[Times@@(n-Select[ cmps,#<n&]),{n,nn}]] (* _Harvey P. Dale_, Aug 13 2024 *)
%Y Cf. A080497, A072513, A080500.
%K nonn
%O 1,6
%A _Amarnath Murthy_, Mar 19 2003
%E More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003