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Least abundant number divisible by the n-th prime number.
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%I #3 Mar 30 2012 17:30:35

%S 12,12,20,42,66,78,102,114,138,174,186,222,246,258,282,318,354,366,

%T 402,426,438,474,498,534,582,606,618,642,654,678,762,786,822,834,894,

%U 906,942,978,1002,1038,1074,1086,1146,1158,1182,1194,1266,1338,1362,1374

%N Least abundant number divisible by the n-th prime number.

%F a(n) = 6*prime(n) for n>=4. - Jose Brox (tautocrona(AT)terra.es), Mar 24 2003

%e 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.

%t If[n==2||n==3, 4, 6]Prime[n]

%K easy,nonn

%O 1,1

%A _Robert G. Wilson v_, Sep 15 2001