Number of non-Abelian metacyclic groups of order 2^n.

Terms

a(0) =0a(1) =0a(2) =2a(3) =5a(4) =9a(5) =15a(6) =22a(7) =32a(8) =43a(9) =57a(10) =72a(11) =91a(12) =110a(13) =134a(14) =158a(15) =187a(16) =216a(17) =251a(18) =285a(19) =326a(20) =366a(21) =413a(22) =459a(23) =513a(24) =565a(25) =626a(26) =685a(27) =753a(28) =819a(29) =895