Start with the list of positive integers 1,2,3,... . After each integer k, insert k empty positions. Fill these positions, from left to right, with the positive integers in order. Repeat this spacing-and-filling process indefinitely. The sequence consists of the positions of the last occurrence of 1 after each step.

A391868

Start with the list of positive integers 1,2,3,... . After each integer k, insert k empty positions. Fill these positions, from left to right, with the positive integers in order. Repeat this spacing-and-filling process indefinitely. The sequence consists of the positions of the last occurrence of 1 after each step.