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A027419
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Number of distinct products i*j with 0 <= i, j <= n-th prime.
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1
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4, 7, 15, 26, 54, 73, 115, 143, 200, 297, 340, 461, 559, 619, 731, 904, 1098, 1178, 1393, 1556, 1652, 1912, 2103, 2391, 2785, 3008, 3150, 3392, 3535, 3789, 4647, 4941, 5363, 5555, 6299, 6495, 6963, 7481, 7864, 8403, 8968, 9196, 10115, 10364, 10805, 11068, 12271
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OFFSET
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1,1
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LINKS
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MAPLE
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PROG
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(Python)
from sympy import prime
def A027419(n): return len({i*j for i in range(1, prime(n)+1) for j in range(1, i+1)})+1 # Chai Wah Wu, Oct 13 2023
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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