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

A247904

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

Terms

    a(0) =1a(1) =6a(2) =21a(3) =56a(4) =131a(5) =286a(6) =601a(7) =1236a(8) =2511a(9) =5066a(10) =10181a(11) =20416a(12) =40891a(13) =81846a(14) =163761a(15) =327596a(16) =655271a(17) =1310626a(18) =2621341a(19) =5242776a(20) =10485651a(21) =20971406a(22) =41942921a(23) =83885956a(24) =167772031a(25) =335544186a(26) =671088501a(27) =1342177136a(28) =2684354411a(29) =5368708966

External references