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A216144
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Square root of smallest square greater than the product of first n primes.
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3
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2, 3, 6, 15, 49, 174, 715, 3115, 14937, 80435, 447840, 2724104, 17442772, 114379900, 784149082, 5708691486, 43849291331, 342473913400, 2803269796342, 23620771158595, 201815957246322, 1793779464521956, 16342108667160302, 154171144824008980, 1518409682511777987
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OFFSET
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1,1
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COMMENTS
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Known values such that a(n)=A145781(n) are a(n)=2,3,6,15 and 715, i.e. for primes p=2,3,5,7 and 17.
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LINKS
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FORMULA
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EXAMPLE
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a(2) = sqrt(2*3 + A145781(2))= sqrt(2*3 + 3) = sqrt(9) = 3.
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PROG
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(PARI) j=[]; for (n=1, 30, p = prod(i=1, n, prime(i)); j=concat(j, floor(sqrt((ceil(sqrt(p))^2)))); ); j
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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