Any kind of repetitive task, including number sequencing, can lead to a decline in conscience thought. Repetitive action demands the brain's attention while providing little stimulation in return. This can cause the mind to effectively shut off.
Focused repetitive activities can have a detrimental effect on the mind. The human brain consists of more than 100 billions cells, all of which are used to form synapses that facilitate the exchange of information.
The brain depends on challenges and tasks that require thought to keep these neuronal pathways alive and active. Repetitive tasks offer no challenge as they need to be executed again and again long after the brain has figured out how to handle them. Repetitive number sequencing can become an automated routine, which no longer requires complex thinking and creative analysis.
Because it can fall back on automated ways of acting and reacting, the brain automatically preserves its energy and essentially goes to sleep on the job. With its attention now focused on an easy and almost unconscious routine, critical thinking is not only completely unnecessary but almost impossible to return to while still performing a repetitive task. This accounts for mindless behavior when performing activities such as repetitive number sequencing.