GCD of consecutive central binomial coefficients: a(n) = gcd(A001405(n+1), A001405(n)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =2a(5) =10a(6) =5a(7) =35a(8) =14a(9) =126a(10) =42a(11) =462a(12) =132a(13) =1716a(14) =429a(15) =6435a(16) =1430a(17) =24310a(18) =4862a(19) =92378a(20) =16796a(21) =352716a(22) =58786a(23) =1352078a(24) =208012a(25) =5200300a(26) =742900a(27) =20058300a(28) =2674440a(29) =77558760