Numbers with exactly 3 ones in both binary and ternary representations.

Terms

a(0) =13a(1) =37a(2) =41a(3) =49a(4) =67a(5) =97a(6) =131a(7) =133a(8) =145a(9) =193a(10) =259a(11) =265a(12) =273a(13) =289a(14) =385a(15) =517a(16) =529a(17) =577a(18) =1027a(19) =1029a(20) =1033a(21) =1041a(22) =1153a(23) =1281a(24) =2053a(25) =2057a(26) =4101a(27) =4105a(28) =4113a(29) =4129