A090090 a(n) = prime(n)*prime(n+3).

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

Author

Felix Tubiana, Jan 21 2004

Keywords

• easy
• nonn

Examples

			a(5) = prime(5)*prime(8) = 11*19 = 209.
		

Crossrefs

Subset of the squarefree semiprimes, A006881.

Cf. A006094, A090076.

Programs

Magma

[NthPrime(n)*NthPrime(n+3): n in [1..40]]; // Vincenzo Librandi, Feb 03 2020

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 *)

Extensions

Extended by Robert G. Wilson v, Jan 22 2004