26767

Appears in sequences

• a(n) = n*(2*n^2 + 5*n + 19)/2.at n=29A163675
• Composite squarefree numbers n such that p(i)-8 divides n+8, where p(i) are the prime factors of n.at n=19A225708
• Composite squarefree numbers n such that p-d(n) divides n+d(n), where p are the prime factors of n and d(n) the number of divisors of n.at n=19A228301
• Numbers k such that (17*10^k - 47)/3 is prime.at n=20A286177
• a(n) = Sum_{k=1..n} k^2*phi(k), where phi is the Euler totient function A000010.at n=19A319087