Numbers of Twopins positions.

Terms

a(0) =1a(1) =2a(2) =3a(3) =5a(4) =8a(5) =13a(6) =22a(7) =37a(8) =63a(9) =108a(10) =186a(11) =322a(12) =559a(13) =973a(14) =1697a(15) =2964a(16) =5183a(17) =9071a(18) =15886a(19) =27835a(20) =48790a(21) =85545a(22) =150021a(23) =263136a(24) =461596a(25) =809812a(26) =1420813a(27) =2492945a(28) =4374273a(29) =7675598