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A126701
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a(n) = number of primes <= !n, where !n is subfactorial n.
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2
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0, 0, 1, 4, 14, 56, 283, 1738, 12457, 102492, 951651, 9830851, 111757480, 1385739200, 18604785172, 268807211509, 4157797131788, 68538901559776, 1199382039260721, 22203590239217092, 433511971123048194, 8902234772796777434, 191798011804919907012
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OFFSET
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1,4
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LINKS
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FORMULA
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EXAMPLE
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a(5) = 14, because !5 = 44 and the number of primes up to 44 is 14.
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CROSSREFS
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KEYWORD
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hard,nonn
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AUTHOR
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EXTENSIONS
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a(21)-a(23) using Kim Walisch's primecount, from Amiram Eldar, Aug 25 2020
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STATUS
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approved
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