Sum of exponents in prime-power factorization of C(4n,2n-2).

Terms

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