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%I #14 Aug 28 2022 14:59:21
%S 1,1,2,6,15,60,140,1260,2772,36036,153153,1225224,3325608,76488984,
%T 212469400,4461857400,11763078600,364655436600,1037865473400,
%U 42552484409400,107632754682600,5058739470082200,33514148989294575,536226383828713200,1665124033994425200
%N a(n) = Product_{k = ceiling(n/2)..n-1} A090252(k).
%C The prime divisors of a(n) are forbidden in A090252(n).
%H Michael De Vlieger, <a href="/A354758/b354758.txt">Table of n, a(n) for n = 1..587</a>
%H Rémy Sigrist, <a href="/A354758/a354758.png">Representation of the prime divisors of a(n) (blue pixels) and A090252(n) (red pixels)</a>
%H Rémy Sigrist, <a href="/A354758/a354758.gp.txt">PARI program</a>
%F gcd(a(n), A090252(n)) = 1.
%e a(7) = A090252(4) * A090252(5) * A090252(6) = 5 * 4 * 7 = 140.
%t With[{s = Import["https://oeis.org/A090252/b090252.txt", "Data"][[1 ;; 25, -1]]}, Table[Product[s[[k]], {k, Ceiling[n/2], n - 1}], {n, Length[s]}]] (* _Michael De Vlieger_, Aug 28 2022 *)
%o (PARI) See Links section.
%Y A355057 is another version.
%Y Cf. A090252, A354757.
%K nonn
%O 1,3
%A _Rémy Sigrist_, Jun 06 2022
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