Tiers du cylindre: the six-split sector

Tiers du cylindre covers 12 pockets on the side of a conventional European wheel opposite zero. Its minimum-chip package puts one unit on each of six splits. Every covered pocket belongs to exactly one selected split, giving the same return whichever covered number wins.

Place six splits

The sector runs in wheel order 27, 13, 36, 11, 30, 8, 23, 10, 5, 24, 16, 33. Its physical sequence differs from the order of the felt split pairs. Our wheel-order reference locates that arc.

Follow a three-chip unit

At three chips per split, total stake is 18. If 23 lands, its split wins 51 chips of profit and returns the original 3. The other five splits lose. Total return is 54 against 18 staked, giving 36 net profit.

At a one-chip unit the same calculation gives 18 returned and 12 net profit. An uncovered result loses all six. On a fair single-zero model the package returns +12 net on 12 pockets and −6 on 25 pockets.

“One third” is approximate

Twelve is one third of the numbered 36, but the wheel includes zero too. The hit probability is 12/37, about 32.43%, rather than exactly one third. Expected profit is 12/37 × 12 minus 25/37 × 6, or −6/37 chips. Divide by six staked and the house edge is 1/37.

Voisins has unequal returns across winning pockets. Orphelins covers the remaining numbers outside those two large sectors. The racetrack overview compares package sizes. Recent absence from a result history does not change this sector's modeled next-spin probability.