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A095209
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a(0) = 1, and for n > 0, a(n) = the least multiple of prime(n) such that the geometric mean of a(0) to a(n) is an integer.
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4
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1, 4, 54, 3750, 504210, 372027810, 144949074270, 209481995953230, 164735296593157290, 401824316553919068810, 2721846739094340967339230, 5095936579799734140259818030, 48850362989361131638352534231610
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OFFSET
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0,2
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LINKS
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FORMULA
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The n-th partial product of these terms = A002110(n)^(1+n), i.e., the n-th geometric mean is the n-th power of (n-1)-th primorial.
a(n) = A057335(A020522(n)). [Found by LODA-miner, follows from the above formulas]
(End)
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EXAMPLE
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(1*4*54*3750)^(1/4) = 30.
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MATHEMATICA
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{1}~Join~MapIndexed[Prime[First[#2]]^First[#2]*#1 &, FoldList[Times, Prime@ Range[12]]] (* Michael De Vlieger, Jul 01 2022 *)
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PROG
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(PARI)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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Starting offset changed from 1 to 0 and the definition accordingly edited by Antti Karttunen, May 04 2022
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STATUS
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approved
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