a(n) is the minimal number of nodes in a binary tree of height n.

Terms

a(0) =0a(1) =1a(2) =2a(3) =4a(4) =6a(5) =9a(6) =12a(7) =17a(8) =22a(9) =29a(10) =36a(11) =46a(12) =56a(13) =69a(14) =82a(15) =100a(16) =118a(17) =141a(18) =164a(19) =194a(20) =224a(21) =261a(22) =298a(23) =345a(24) =392a(25) =449a(26) =506a(27) =576a(28) =646a(29) =729