OFFSET
1,1
COMMENTS
Starting with n=10, n-th even semiprime > n-th odd semiprime. Sequence is not monotonic, with general increasing trend.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
MATHEMATICA
Module[{semis=Select[Range[1000], PrimeOmega[#]==2&], ev, od, len}, ev = Select[ semis, EvenQ]; od=Select[semis, OddQ]; len=Min[Length[ ev], Length[ od]]; First[#]- Last[#]&/@Thread[{Take[ev, len], Take[od, len]}]] (* Harvey P. Dale, Apr 20 2014 *)
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Zak Seidov, Oct 02 2007
STATUS
approved