OFFSET
1,1
COMMENTS
It is conjectured that every semiprime will appear.
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..10000
Rémy Sigrist, PARI program for A338309
MATHEMATICA
sp = Select[Range[4, 500], 2 == PrimeOmega[#] &]; s = {4}; a = 4;
Do[Do[b = sp[[k2]]; If[FreeQ[s, b] && 2 == PrimeOmega[a + b], AppendTo[s, (a = b)]; Break[]], {k2, Length[sp]}], {k1, 70}]; s
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Oct 22 2020
STATUS
approved