a(n) = A014486(A122241(n)).

Terms

a(0) =42a(1) =240a(2) =916a(3) =3748a(4) =14960a(5) =62104a(6) =248176a(7) =969304a(8) =3876576a(9) =15962544a(10) =63772488a(11) =248169896a(12) =993554240a(13) =4086635408a(14) =16350541128a(15) =63529835824a(16) =254129143040