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A216600 Number of ways to write n as a product with all factors <= n/4.

%I A216600 #6 Jul 13 2013 12:04:31
%S A216600 0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,3,0,1,0,2,0,0,0,4,1,0,1,2,0,2,0,5,0,0,
%T A216600 1,6,0,0,0,5,0,2,0,2,2,0,0,9,1,2,0,2,0,4,1,5,0,0,0,8,0,0,2,9,1,2,0,2,
%U A216600 0,3,0,13,0,0,2,2,1,2,0,10,3,0,0,8,1,0
%N A216600 Number of ways to write n as a product with all factors <= n/4.
%C A216600 a(n) = A066032(n,floor(n/4)) for n > 3.
%H A216600 Reinhard Zumkeller, <a href="/A216600/b216600.txt">Table of n, a(n) for n = 1..1000</a>
%e A216600 a(40) = #{10*4, 10*2*2, 8*5, 5*4*2, 5*2*2*2} = 5;
%e A216600 a(41) = #{} = 0;
%e A216600 a(42) = #{7*6, 7*3*2} = 2;
%e A216600 a(43) = #{} = 0;
%e A216600 a(44) = #{11*4, 11*2*2} = 2;
%e A216600 a(45) = #{9*5, 5*3*3} = 2.
%o A216600 (Haskell)
%o A216600 a216600 n | n <= 3    = 0
%o A216600           | otherwise = a066032_tabl !! (n-1) !! (n `div` 4 - 1)
%Y A216600 Cf. A001055, A028422, A216599, A216601, A216602.
%K A216600 nonn
%O A216600 1,16
%A A216600 _Reinhard Zumkeller_, Oct 01 2012