OFFSET
1,1
LINKS
K. D. Bajpai, Table of n, a(n) for n = 1..9646
Wikipedia, Ternary numeral system
EXAMPLE
65 is in the sequence because 5*13 = 65 (semiprime) and its ternary representation, 2102 = 2*1051, when read as a decimal number, is also semiprime.
115 is in the sequence because 5*23 = 115 (semiprime) and its ternary representation, 11021 = 103*107, when read as a decimal number, is also semiprime.
MATHEMATICA
Select[Range[5000], PrimeOmega[#] == 2 && PrimeOmega[FromDigits[ IntegerDigits[ #, 3]]] == 2 &]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
K. D. Bajpai, Dec 04 2016
STATUS
approved