22649

Appears in sequences

• Smallest k>1 such that k(p-1)-1 is divisible by p^2, p=n-th prime.at n=35A039914
• p^2-p-1 that is not prime, where p is prime.at n=18A119609
• a(n) = least k such that the remainder when 17^k is divided by k is n.at n=45A128157
• a(n) = a(n-1) + a(n-2) + a(n-3) with a(0)=2, a(1)=1, a(2)=2.at n=17A214899
• Numbers m such that the decimal number concat(8,m) is a square.at n=29A273363
• Odd squarefree numbers n > 1 such that lambda(n)^2 = phi(n), where lambda is the Carmichael lambda function and phi is Euler's totient function.at n=21A276980
• a(n) = (prime(1+n)*prime(n)) + prime(n) + 1.at n=34A286624
• a(n) = p^2 - p - 1 where p = prime(n), the n-th prime.at n=35A306190
• Maximally idempotent integers with three or more factors.at n=35A306812
• a(n) = (p_n + 1)*q_n - 1; where (p_n, q_n) is the n-th twin prime pair.at n=11A328493
• Products of three distinct strong primes.at n=17A363782