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A090090
a(n) = prime(n)*prime(n+3).
7
14, 33, 65, 119, 209, 299, 493, 589, 851, 1189, 1333, 1739, 2173, 2537, 2867, 3551, 4189, 4453, 5293, 5893, 6497, 7663, 8383, 9167, 10379, 11009, 11639, 13589, 14279, 15481, 17653, 19519, 20687, 21823, 24287, 25217, 27161, 29177, 30227, 33043
OFFSET
1,1
EXAMPLE
a(5) = prime(5)*prime(8) = 11*19 = 209.
MATHEMATICA
Table[ Prime[n] Prime[n + 3], {n, 1, 40}] (* Robert G. Wilson v, Jan 22 2004 *)
First[#]*Last[#]&/@Partition[Prime[Range[200]], 4, 1] (* Harvey P. Dale, Dec 18 2011 *)
PROG
(Magma) [NthPrime(n)*NthPrime(n+3): n in [1..40]]; // Vincenzo Librandi, Feb 03 2020
CROSSREFS
Subset of the squarefree semiprimes, A006881.
Sequence in context: A191866 A162279 A367346 * A116150 A019272 A018949
KEYWORD
easy,nonn
AUTHOR
Felix Tubiana, Jan 21 2004
EXTENSIONS
Extended by Robert G. Wilson v, Jan 22 2004
STATUS
approved