First numerator and then denominator of central elements of Leibniz's Harmonic Triangle.

Terms

a(0) =1a(1) =1a(2) =1a(3) =6a(4) =1a(5) =30a(6) =1a(7) =140a(8) =1a(9) =630a(10) =1a(11) =2772a(12) =1a(13) =12012a(14) =1a(15) =51480a(16) =1a(17) =218790a(18) =1a(19) =923780a(20) =1a(21) =3879876a(22) =1a(23) =16224936a(24) =1a(25) =67603900a(26) =1a(27) =280816200a(28) =1a(29) =1163381400