Concatenate consecutive prime-sided isosceles triangles.

Terms

a(0) =233a(1) =355a(2) =577a(3) =71111a(4) =111313a(5) =131717a(6) =171919a(7) =192323a(8) =232929a(9) =293131a(10) =313737a(11) =374141a(12) =414343a(13) =434747a(14) =475353a(15) =535959a(16) =596161a(17) =616767a(18) =677171a(19) =717373a(20) =737979a(21) =798383a(22) =838989a(23) =899797a(24) =97101101a(25) =101103103a(26) =103107107a(27) =107109109a(28) =109113113