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

Terms

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