290026618domain: NAppears in sequencesApproximation of the 2-adic integer arctanh(2) up to 2^n.at n=29A309753Approximation of the 2-adic integer arctanh(2) up to 2^n.at n=30A309753Approximation of the 2-adic integer arctanh(2) up to 2^n.at n=31A309753