Terms in A061725 that are of form 3*prime.

Terms

a(0) =6a(1) =51a(2) =123a(3) =291a(4) =843a(5) =1371a(6) =1851a(7) =2811a(8) =5331a(9) =6243a(10) =6891a(11) =9411a(12) =18771a(13) =36483a(14) =54291a(15) =63003a(16) =69171a(17) =72363a(18) =73443a(19) =76731a(20) =78963a(21) =128883a(22) =143643a(23) =151323a(24) =187491a(25) =212523a(26) =229443a(27) =271443a(28) =292683a(29) =332931