A362915 a(n) = size of largest subset of {1...n} such that no difference between two terms is a prime + 1.

1, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 11, 12, 12, 12, 12, 12, 12, 12

Offset: 1

Author

N. J. A. Sloane, May 15 2023

Keywords

• nonn

Comments

Suggested by Ben Green's Number Theory Web Seminar on May 11 2023.

Links

• Ben Green, On Sarkozy's theorem for shifted primes, Number Theory Web Seminar, May 11 2023; Youtube video https://www.youtube.com/watch?v=5JH_YshJoCo.

Crossrefs

Other entries of the form "size of largest subset of {1...n} such that no difference between two terms is ...": a square: A100719; a prime - 1: A131849; a prime: A362914.

Extensions

a(1)-a(40) from Zachary DeStefano, May 15 2023, a(41)-a(100) from Rob Pratt, May 15 2023.