1246785

Appears in sequences

• Increasing gaps between 2-pseudoprimes (upper end).at n=19A175737
• Fermat pseudoprimes to base 2 of the form (n^2 + 2*n)/3.at n=25A216170
• Fermat pseudoprimes to base 2 divisible by 15.at n=9A216364
• Fermat pseudoprimes to base 2 that can be written as p^2*n - p*n + p, where p is also a Fermat pseudoprime to base 2 and n is a positive integer.at n=2A217835
• a(n) = n*(3*n - 2)*(9*n^2 - 6*n - 2).at n=15A264892
• Fermat pseudoprimes to base 2 that are octagonal.at n=25A321868