Barlow packings with group R3(bar)m(SO) that repeat after 6n+3 layers.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =11a(5) =20a(6) =42a(7) =84a(8) =170a(9) =340a(10) =682a(11) =1364a(12) =2728a(13) =5461a(14) =10922a(15) =21844a(16) =43690a(17) =87374a(18) =174762a(19) =349524a(20) =699050a(21) =1398100a(22) =2796192a(23) =5592404a(24) =11184806a(25) =22369620a(26) =44739242a(27) =89478462a(28) =178956970a(29) =357913940