A092576 a(n) = the least number which is the average of two consecutive primes and has exactly n prime factors (counted with multiplicity).

4, 12, 56, 72, 64, 192, 960, 1152, 3840, 7168, 4096, 30720, 36864, 110592, 360448, 663552, 2064384, 786432, 3932160, 5242880, 9437184, 63700992, 138412032, 169869312, 436207616, 3875536896, 1358954496, 1879048192, 10066329600, 8053063680, 14495514624

Offset: 2

Author

Zak Seidov, Feb 29 2004

Keywords

• nonn

Comments

The sequence is non-monotonic: a(6)

Examples

			a(3)=12 because 12=(11+13)/2 and 12=2*2*3 has 3 prime factors.
		

Links

• Donovan Johnson, Table of n, a(n) for n = 2..300

Crossrefs

Cf. A024675, A078443.

Programs

Mathematica

Flatten[With[{m=Mean/@Partition[Prime[Range[2,370000]],2,1]},Table[ Select[ m,PrimeOmega[#]==n&,1],{n,2,20}]]] (* To generate 30 rather than 20 terms of the sequence, change 370000 to 458000000 and 20 to 30. *) (* Harvey P. Dale, Jun 22 2013 *)

Extensions

Edited by Don Reble, Mar 17 2007

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