Rogozhin (4,6) Machine

Rogozhin's 4-state, 6-symbol universal Turing machine (1996), running on a self-growing tape.

Sync Tick Turing

Try it live→ Download Database

Machine replay — the (4,6) head over a six-symbol tape FULLSCREEN ⤢

Clock Tick — one step per turn

Update Synchronous

States 4 (A–D)

Symbols 6

Halts Has a halt state

OVERVIEW

Rogozhin's (4,6) universal machine as a true Turing machine. Four states A–D over a six-symbol alphabet drive the head across a bidirectional, self-growing tape. Rogozhin's family of small universal machines pinned down how few states and symbols a universal Turing machine needs; this scenario runs that machine's exact transition table on a plain, un-encoded input so the six-symbol dynamics are visible step by step.

The largest transition table in the Turing set — four states by six symbols — and a stress test of the modelling pattern at width. The same self-growing tape that carries a two-symbol machine carries a six-symbol one unchanged; only the head's table grows. We make no claim that this input drives a specific universal computation — it is the well-defined initial condition on which the authentic dynamics are shown.

TRAITS

Sync

Advances on a single global clock

Tick

Discrete fixed-step time

Turing

A head reads & writes an unbounded tape

SCHEMA

Linked tables with guaranteed referential integrity.

TABLECOLUMNSDESCRIPTION

cell ID, symbol, has_left, has_right, left_id, right_id, current_state One row per tape square over six symbols, with self-built left/right neighbour references.

head ID, current_id, nc, current_state The read/write head: the cell beneath it and its A–D control state.

LIVE API

Generated REST endpoints. Also exposed as MCP tools.

POST /scenarios/rogozhin-46/experiments Seed a fresh tape and head

POST /scenarios/rogozhin-46/experiments/{eid}/run Advance the machine N steps

GET /scenarios/rogozhin-46/experiments/{eid}/entities/cell Read the tape, one row per square

GET /scenarios/rogozhin-46/experiments/{eid}/events Append-only step log

GET /scenarios/rogozhin-46/experiments/{eid}/dataset Download the exported dataset

SEMANTIC LAYER

OSI-compatible definition, emitted with the dataset.

# rogozhin-46.osi.yaml — emitted automatically
semantic_model:
  name: "rogozhin-46"
  source: "duckdb://rogozhin-46.db"
  entities:
    - name: cell
      primary_key: id
  dimensions:
    - name: state
      type: categorical
    - name: t
      type: time
  measures:
    - name: row_count
      agg: count
    - name: active
      agg: sum
      filter: "state = 'ACTIVE'"