Sum of exponents in prime-power factorization of C(2n,n-1).

Terms

a(0) =0a(1) =2a(2) =2a(3) =4a(4) =4a(5) =6a(6) =4a(7) =7a(8) =6a(9) =7a(10) =6a(11) =9a(12) =8a(13) =11a(14) =9a(15) =12a(16) =9a(17) =13a(18) =10a(19) =13a(20) =12a(21) =13a(22) =12a(23) =15a(24) =14a(25) =14a(26) =14a(27) =16a(28) =14a(29) =17