91081

Properties

Appears in sequences

• Group the natural numbers so that the product of the terms in each group + 1 is a prime: (1), (2), (3, 4), (5, 6), (7, 8, 9, 10, 11), (12), (13, 14, 15), (16), ... This is the sequence of such primes.at n=14A073688
• Class 7+ primes.at n=23A081635
• Primes of the form k^3 - k + 1.at n=18A100698
• Prime numbers p such that pi(p) + 2*p is a square.at n=26A104783
• Secondary diagonal of square table A112564 of generalized Flavius Josephus sieves.at n=8A112568
• Primes of the form x^2 + 18480*y^2.at n=26A173274
• Fixed points of A245821 and A245822.at n=31A245823
• Primes of the form (k - 1) * k * (k + 1) +- 1, k >= 1.at n=38A293861
• Numbers k such that -3 is a quadratic residue (not necessarily coprime) modulo k, k + 1, k + 2 and k + 3.at n=51A318527
• Prime numbersat n=8807