Number of symmetrical fountains of n coins.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =1a(5) =3a(6) =3a(7) =5a(8) =4a(9) =9a(10) =8a(11) =15a(12) =14a(13) =26a(14) =24a(15) =46a(16) =42a(17) =79a(18) =73a(19) =137a(20) =128a(21) =239a(22) =221a(23) =414a(24) =385a(25) =719a(26) =668a(27) =1249a(28) =1161a(29) =2167