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%I #9 Aug 23 2019 14:10:03
%S 1,1,1,1,2,2,6,6,8,12,30,30,48,48,112,210,240,240,324,324,480,840,
%T 1848,1848,2304,2880,6240,7020,10080,10080,14400,14400,15360,25344,
%U 53856,78540,90720,90720,191520,311220,374400,374400,508032,508032,709632,855360,1788480,1788480
%N a(n) = Product_{p prime, p <= n} floor(n/p).
%C Product of exponents of prime factorization of A048803 (squarefree factorials).
%F a(n) = Product_{k=1..A000720(n)} floor(n/A000040(k)).
%F a(n) = A005361(A048803(n)).
%e A048803(14) = 1816214400 = 2^7 * 3^4 * 5^2 * 7^2 * 11 * 13 so a(14) = 7 * 4 * 2 * 2 * 1 * 1 = 112.
%p a:= n-> mul(floor(n/p), p=select(isprime, [$2..n])):
%p seq(a(n), n=0..50); # _Alois P. Heinz_, Aug 23 2019
%t Table[Product[Floor[n/Prime[k]], {k, 1, PrimePi[n]}], {n, 0, 47}]
%Y Cf. A000040, A000720, A005361, A010786, A013939, A048803, A135291.
%K nonn
%O 0,5
%A _Ilya Gutkovskiy_, Aug 22 2019