a(n) = A215082(2*n+1).

Terms

a(0) =1a(1) =3a(2) =5a(3) =12a(4) =23a(5) =43a(6) =81a(7) =148a(8) =266a(9) =476a(10) =842a(11) =1478a(12) =2581a(13) =4481a(14) =7743a(15) =13328a(16) =22857a(17) =39073a(18) =66605a(19) =113242a(20) =192084a(21) =325128a(22) =549252a(23) =926220a(24) =1559353a(25) =2621295a(26) =4400249a(27) =7376868a(28) =12352043a(29) =20659159