Implement recursive algorithms with sub-workflows: Towers of Hanoi demo

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Important notice

This workflow is provided as-is. Please review and test before using in production.

1. Workflow Overview

How it works This is an example of using sub workflow nodes and a proof of concept showing that it’s possible to solve and explain recursive problems with n8n . Towers of Hanoi Task Move a stack of...

Best for

Engineering automation workflows
Multimodal AI automation workflows
advanced n8n builders looking for reusable templates

Tools used

n8n-nodes-base.set, n8n-nodes-base.if, n8n-nodes-base.executeworkflow, n8n-nodes-base.executeworkflowtrigger, n8n-nodes-base.code, n8n-nodes-base.stickynote, n8n-nodes-base.manualtrigger

Source and attribution

This workflow is cataloged by N8N Workflows and links back to its original n8n.io source page by Adrian.

Original n8n.io source

1.1 Workflow description

Title: Implement recursive algorithms with sub-workflows: Towers of Hanoi demo
Workflow name: Implement recursive algorithms with sub-workflows: Towers of Hanoi demo

How it works

This is an example of using sub-workflow nodes and a proof of concept showing that it’s possible to solve and explain recursive problems with n8n.

Towers of Hanoi - Task

Move a stack of n disks from rod A to rod C, using rod B as auxiliary. Only one disk can be moved at a time, and no disk may be placed on a smaller disk.

Example

n=4
     |          |          |
     =          |          |
    ===         |          |
   =====        |          |
  =======       |          |
 ---------  ---------  ---------
     A          B          C

Algorithm

procedure Hanoi(n, X, Y, Z):
  if n == 1:
    move disk from X to Z
  else:
    Hanoi(n-1, X, Z, Y)
    move disk from X to Z
    Hanoi(n-1, Y, X, Z)

Notes

This is a learning example. In a real scenario, you would probably use an iterative approach with only a single code node.
When experimenting with recursion, make sure to define a termination condition first. Also, be aware of the "Restart workspace" link in the n8n Dashboard.
Learn more about Recursion on Wikipedia.

Set up steps

Optional: Set "numberOfDiscs" in node "Set number of discs"
Execute workflow

1.2 Logical Blocks

This catalog entry is organized from the workflow JSON. The node-level section below shows the executable blocks available for review before importing the template.

2. Block-by-Block Analysis

Block 1 - Set number of discs

Type / Role: n8n-nodes-base.set - set
Config choices: Version 3.4

Block 2 - Max 1 disc

Type / Role: n8n-nodes-base.if - if
Config choices: Version 2.2

Block 3 - A B C

Type / Role: n8n-nodes-base.executeWorkflow - executeWorkflow
Config choices: Version 1.2

Block 4 - X Y Z

Type / Role: n8n-nodes-base.executeWorkflowTrigger - executeWorkflowTrigger
Config choices: Version 1.1

Block 5 - X to Z

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 6 - X to Z

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 7 - Update

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 8 - Update

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 9 - Create stacks

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 10 - X Z Y

Type / Role: n8n-nodes-base.executeWorkflow - executeWorkflow
Config choices: Version 1.2

Block 11 - Y X Z

Type / Role: n8n-nodes-base.executeWorkflow - executeWorkflow
Config choices: Version 1.2

Block 12 - Solution

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 13 - user input

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 14 - setup

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 15 - result

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 16 - solution

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 17 - swap

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 18 - move

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 19 - update

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 20 - Start

Type / Role: n8n-nodes-base.manualTrigger - manualTrigger
Config choices: Version 1

Block 21 - Towers of Hanoi

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

3. Summary Table

Workflow	Implement recursive algorithms with sub-workflows: Towers of Hanoi demo
Complexity	advanced
Nodes	21
Categories	Engineering, Multimodal AI
Author	Adrian
Published	16 Sept 2025

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

Use the JSON export at /data/workflows/8656/8656.json as the source template for this automation.
2. Import the template into n8n

Open n8n, import the downloaded JSON, and review each node before activating the workflow.
3. Configure credentials and variables

Replace placeholder credentials, API keys, webhook URLs, account IDs, and environment-specific values with your own settings.
4. Test with sample data

Run the workflow manually or in a staging workspace, inspect node output, and confirm downstream systems receive the expected data.
5. Activate and monitor

Enable the workflow only after testing, then monitor executions, errors, and rate limits during the first production runs.

5. General Notes & Resources

Review imported nodes carefully before activation. This catalog entry is intended to help you inspect the workflow structure, understand required services, and find related templates faster.

Node names, credentials, schedules, webhook paths, and external service limits may need adjustment for your workspace.

Download workflow JSON Original n8n.io source Engineering workflows Multimodal AI workflows

Frequently asked questions

What does Implement recursive algorithms with sub-workflows: Towers of Hanoi demo do?

What do I need before importing this workflow?

Review the workflow JSON, configure any required credentials in n8n, and test the automation in a safe workspace before using it in production.

Can I customize this workflow?

Yes. Use the block-by-block analysis and the downloadable JSON to inspect each node, then adjust credentials, prompts, schedules, filters, or destinations for your Engineering, Multimodal AI use case.

Adrian

1 workflow

Nodes

n8n-nodes-base.set n8n-nodes-base.if n8n-nodes-base.executeworkflow n8n-nodes-base.executeworkflowtrigger n8n-nodes-base.code n8n-nodes-base.stickynote n8n-nodes-base.manualtrigger

Complexity

advanced

Published 16 Sept 2025

Likes 0

View on n8n.io Download Workflow

Install path: /data/workflows/8656/8656.json

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Implement recursive algorithms with sub-workflows: Towers of Hanoi demo

Workflow preview

Important notice

1. Workflow Overview

Best for

Tools used

Source and attribution

1.1 Workflow description

How it works

Towers of Hanoi - Task

Example

Algorithm

Notes

Set up steps

1.2 Logical Blocks

2. Block-by-Block Analysis

Block 1 - Set number of discs

Block 2 - Max 1 disc

Block 3 - A B C

Block 4 - X Y Z

Block 5 - X to Z

Block 6 - X to Z

Block 7 - Update

Block 8 - Update

Block 9 - Create stacks

Block 10 - X Z Y

Block 11 - Y X Z

Block 12 - Solution

Block 13 - user input

Block 14 - setup

Block 15 - result

Block 16 - solution

Block 17 - swap

Block 18 - move

Block 19 - update

Block 20 - Start

Block 21 - Towers of Hanoi

3. Summary Table

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

2. Import the template into n8n

3. Configure credentials and variables

4. Test with sample data

5. Activate and monitor

5. General Notes & Resources

Frequently asked questions