a(n) = (p+2)!/p! where p is the n-th lesser twin prime, A001359(n).

Terms

a(0) =20a(1) =42a(2) =156a(3) =342a(4) =930a(5) =1806a(6) =3660a(7) =5256a(8) =10506a(9) =11772a(10) =19182a(11) =22650a(12) =32580a(13) =37056a(14) =39402a(15) =52212a(16) =57840a(17) =73170a(18) =79806a(19) =97656a(20) =121452a(21) =176820a(22) =187056a(23) =213906a(24) =273006a(25) =325470a(26) =360600a(27) =382542a(28) =412806a(29) =436260