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A064161
Least abundant number divisible by the n-th prime number.
0
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
OFFSET
1,1
FORMULA
a(n) = 6*prime(n) for n>=4. - Jose Brox (tautocrona(AT)terra.es), Mar 24 2003
EXAMPLE
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.
MATHEMATICA
If[n==2||n==3, 4, 6]Prime[n]
CROSSREFS
Sequence in context: A334620 A061074 A372219 * A260528 A260526 A040133
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Sep 15 2001
STATUS
approved