OFFSET
1,1
COMMENTS
This is the semiprime analog of A064402.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
Eric Weisstein, World of Mathematics, Semiprime.
EXAMPLE
a(3) = 9 because 9 + semiprime(9) = 9 + 25 = 34 is semiprime.
MATHEMATICA
With[{c=Select[Range[1000], PrimeOmega[#]==2&]}, Transpose[Select[Thread[ {c, Range[ Length[c]]}], PrimeOmega[Total[#]]==2&]][[2]]] (* Harvey P. Dale, Oct 25 2011 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Ray Chandler, Nov 26 2004
STATUS
approved