3 4c 7 12 7 24c 2 3 July 8, 2019 16 32 64 128 3 4c 7 12 7 24c 2 3 1 6c 2c(3c – 7) – (c – 1)(c + 4) 2 9c-4 7d+4 3-3 4c+3 1d
