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A354758
a(n) = Product_{k = ceiling(n/2)..n-1} A090252(k).
5
1, 1, 2, 6, 15, 60, 140, 1260, 2772, 36036, 153153, 1225224, 3325608, 76488984, 212469400, 4461857400, 11763078600, 364655436600, 1037865473400, 42552484409400, 107632754682600, 5058739470082200, 33514148989294575, 536226383828713200, 1665124033994425200
OFFSET
1,3
COMMENTS
The prime divisors of a(n) are forbidden in A090252(n).
FORMULA
gcd(a(n), A090252(n)) = 1.
EXAMPLE
a(7) = A090252(4) * A090252(5) * A090252(6) = 5 * 4 * 7 = 140.
MATHEMATICA
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 *)
PROG
(PARI) See Links section.
CROSSREFS
A355057 is another version.
Sequence in context: A027287 A192186 A243550 * A003268 A242792 A216811
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Jun 06 2022
STATUS
approved