Numerator of Bernoulli(n, 1/4).

Terms

a(0) =1a(1) =-1a(2) =-1a(3) =3a(4) =7a(5) =-25a(6) =-31a(7) =427a(8) =127a(9) =-12465a(10) =-2555a(11) =555731a(12) =1414477a(13) =-35135945a(14) =-57337a(15) =2990414715a(16) =118518239a(17) =-329655706465a(18) =-5749691557a(20) =91546277357