the.com/arithmetic sequence
Numbers walking in a straight line, same stride every step forever.
means A list of numbers where you get the next one by adding (or subtracting) the same fixed amount every time, like 2, 5, 8, 11.
from From Greek 'arithmos' meaning 'number,' which gave rise to 'arithmetike (tekhne)' — 'the art of counting.' The word traveled through Latin 'arithmetica' and into Old French before landing in English around the 14th century. 'Sequence' comes from Latin 'sequi,' 'to follow' — the same root behind 'sequel' and 'consequence.' So the phrase is quite literally 'numbers that follow' in a countable, orderly way — fitting for a concept built on dutiful, repeated addition.
- the rule
- add a fixed number each time, no exceptions
- nth term
- a1 plus (n-1) times d, no counting required
- contrast
- geometric sequences multiply, these only add
- real use
- compound interest is geometric, your paycheck raise is arithmetic