Week 2, the options will be different every time so its fun.

I will make these markets start every week and last 2 weeks, so there will be two concurrent markets at the same time.

Here are lists of these numbers under 100:

Numbers below 12: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11

Triangular numbers: 0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91

Semiprimes: 4, 6, 9, 10, 14, 15, 21, 22, 25, 26, 33, 34, 35, 38, 39, 46, 49, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, 85, 86, 87, 91, 93, 94, 95

Lucas numbers: 1, 2, 3, 4, 7, 11, 18, 29, 47, 76

Between 5 and 10 inclusive: 5, 6, 7, 8, 9, 10

The form 2^b ± 1 for some integer b: 0, 1, 2, 3, 5, 7, 9, 15, 17, 31, 33, 63, 65
Lucky numbers: 1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 69, 73, 75, 79, 87, 93, 99

Strobogrammatic numbers: 0, 1, 8, 11, 69, 88, 96

Amenable numbers: 0, 1, 5, 8, 9, 12, 13, 16, 17, 20, 21, 24, 25, 28, 29, 32, 33, 36, 37, 40, 41, 44, 45, 48, 49, 52, 53, 56, 57, 60, 61, 64, 65, 68, 69, 72, 73, 76, 77, 80, 81, 84, 85, 88, 89, 92, 93, 96, 97

Contains only the digits 0 and 1 in base 3: 0, 1, 3, 4, 9, 10, 12, 13, 27, 28, 30, 31, 36, 37, 39, 40, 81, 82, 84, 85, 90, 91, 93, 94