Start with a single hexagon; at n-th generation add a hexagon at each expandable vertex; a(n) is the sum of all label values at n-th generation. (See comment for construction rules.)

A247620

Start with a single hexagon; at n-th generation add a hexagon at each expandable vertex; a(n) is the sum of all label values at n-th generation. (See comment for construction rules.)

Terms

    a(0) =1a(1) =7a(2) =25a(3) =67a(4) =157a(5) =343a(6) =721a(7) =1483a(8) =3013a(9) =6079a(10) =12217a(11) =24499a(12) =49069a(13) =98215a(14) =196513a(15) =393115a(16) =786325a(17) =1572751a(18) =3145609a(19) =6291331a(20) =12582781a(21) =25165687a(22) =50331505a(23) =100663147a(24) =201326437a(25) =402653023a(26) =805306201a(27) =1610612563a(28) =3221225293a(29) =6442450759

External references