Approximation of the 2-adic integer arctan(4) up to 2^n.

Terms

a(0) =0a(1) =0a(2) =0a(3) =4a(4) =4a(5) =4a(6) =4a(7) =68a(8) =68a(9) =324a(10) =324a(11) =324a(12) =2372a(13) =2372a(14) =2372a(15) =18756a(16) =51524a(17) =51524a(18) =182596a(19) =444740a(20) =969028a(21) =2017604a(22) =4114756a(23) =4114756a(24) =4114756a(25) =20891972a(26) =20891972a(27) =20891972a(28) =20891972a(29) =289327428