How Many Well/Total Orders?

Let A A be the number of totally-ordered sets below, and let B B be the number of well-ordered sets below. What is A + B A+B ?

  • S = R S = \mathbb{R} with the standard order.

  • S = 2 R S = 2^{\mathbb{R}} , the power set of R \mathbb{R} , ordered by set inclusion, i.e. A B A \le B iff A B A \subseteq B .

  • S = R 2 S = \mathbb{R}^2 with the dictionary order.

  • S = N S = \mathbb{N} , with the order given by 3 × 2 0 , 3 × 2 1 , 3 × 2 2 , , 5 × 2 0 , 5 × 2 1 , 5 × 2 2 , , 7 × 2 0 , 7 × 2 1 , 7 × 2 2 , , 9 × 2 0 , 9 × 2 1 , 9 × 2 2 , , , 1 × 2 2 , 1 × 2 1 , 1 × 2 0 . \begin{array} { l l l l l l } 3 \times 2^0, & 3 \times 2^1 , & 3 \times 2^2, & \ldots, \\ 5 \times 2^0, & 5 \times 2^1 , & 5 \times 2^2, & \ldots, \\ 7\times 2^0, & 7 \times 2^1 , & 7 \times 2^2, & \ldots, \\ 9 \times 2^0, & 9 \times 2^1 , & 9 \times 2^2, & \ldots, \\ \vdots& \\ \ldots, & 1 \times 2^2, & 1 \times 2^1 , & 1 \times 2^0. \end{array}

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