• 1 + 1 + 1 + 1 + ⋯
• 1 − 2 + 3 − 4 + ⋯
• 1 + 2 + 3 + 4 + ⋯
• 1 + 2 + 4 + 8 + ⋯
• 1 − 2 + 4 − 8 + ⋯
• 1 − 1 + 2 − 6 + 24 − 120 + ⋯

i really like that these don't have names so the article title is literally just the first few terms of the series yet someone found it important enough to make an article on each one lmao