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A355516
a(n) is the number of distinct integer values of Product_{k=1..n} (2 + 1/t_k) with integers t_k > 1.
2
1, 2, 5, 11, 29, 70, 164, 392, 933
OFFSET
2,2
EXAMPLE
a(2) = 1: The only representable integer is 5 = (2 + 1/3) * (2 + 1/7).
a(3) = 2: 9 and 11 can be represented; 9 = (2 + 1/9) * (2 + 1/13) * (2 + 1/19) and 10 other ways; 11 = (2 + 1/3)*(2 + 1/5)*(2 + 1/7) = (2 + 1/3)^2 * (2 + 1/49).
PROG
(PARI) see link in A355626.
CROSSREFS
A355626 provides more information.
A355628 same problem with factors (3 + 1/t_k).
Cf. A355243.
Sequence in context: A215939 A309857 A117719 * A359661 A316769 A192785
KEYWORD
nonn,hard,more
AUTHOR
Hugo Pfoertner and Markus Sigg, Jul 16 2022
STATUS
approved