|
Search: id:A064161
|
|
|
| A064161 |
|
Least abundant number divisible by the n-th prime number. |
|
+0
1
|
|
| 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
(list; graph; listen)
|
|
|
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: A056627 A061074 A134324 this_sequence A040133 A092538 A022346
Adjacent sequences: A064158 A064159 A064160 this_sequence A064162 A064163 A064164
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 15 2001
|
|
|
Search completed in 0.002 seconds
|
