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A064161
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Least abundant number divisible by the n-th prime number.
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0
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12, 12, 20, 42, 66, 78, 102, 114, 138, 174, 186, 222, 246, 258, 282, 318, 354, 366, 402, 426, 438, 474, 498, 534, 582, 606, 618, 642, 654, 678, 762, 786, 822, 834, 894, 906, 942, 978, 1002, 1038, 1074, 1086, 1146, 1158, 1182, 1194, 1266, 1338, 1362, 1374
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OFFSET
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1,1
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LINKS
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FORMULA
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a(n) = 6*prime(n) for n>=4. - Jose Brox (tautocrona(AT)terra.es), Mar 24 2003
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EXAMPLE
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The first eight abundant numbers are 12, 18, 20, 24, 30, 36, 40 and 42. But only the last one is divisible by 7, the fourth prime number. Therefore a(4) = 42.
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MATHEMATICA
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If[n==2||n==3, 4, 6]Prime[n]
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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