135970

Appears in sequences

• Number of permutations p of {1,...,n} satisfying p(1)=1 and, if n>1, |p(i)-p((i mod n)+1)| is in {2,3} for i from 1 to n.at n=51A174469
• Starts of runs of 3 consecutive Catalan-Niven numbers (A352508).at n=25A352510