From higher-order Bernoulli numbers: denominator of the D-number D2n(2n-1).

Terms

a(0) =3a(1) =5a(2) =21a(3) =45a(4) =11a(5) =1365a(6) =45a(7) =51a(8) =399a(9) =3465a(10) =345a(11) =20475a(12) =189a(13) =145a(14) =7161a(15) =58905a(16) =105a(17) =27417a(18) =117a(19) =6765a(20) =148995a(21) =108675a(22) =329a(23) =2436525a(24) =65637a(25) =26235a(26) =21945a(27) =4959a(28) =177a(29) =85180095