Numbers having four 3's in base 4.

Terms

a(0) =255a(1) =511a(2) =767a(3) =831a(4) =895a(5) =959a(6) =975a(7) =991a(8) =1007a(9) =1011a(10) =1015a(11) =1019a(12) =1020a(13) =1021a(14) =1022a(15) =1279a(16) =1535a(17) =1791a(18) =1855a(19) =1919a(20) =1983a(21) =1999a(22) =2015a(23) =2031a(24) =2035a(25) =2039a(26) =2043a(27) =2044a(28) =2045a(29) =2046