18745

Appears in sequences

• Largest eigenvalue, rounded to the nearest integer, of a rank n matrix of 1..n^2 filled successively along antidiagonals (A069480).at n=31A072332
• Composite numbers coprime to 6 such that A179382(n) = A000265(n-1), the odd part of n-1.at n=28A225913
• Products of 3 evil primes (A027699) p,q,r, such that numbers p*q, p*r, q*r, and p*q*r are odious (A000069).at n=22A230353
• Number of compositions of 2*n with n maximal anti-runs.at n=11A337504
• Numbers k such that the sum of k, the divisors of k, and the numbers < k that are coprime to k, is a perfect power.at n=7A352876
• Numbers k such that k^6*2^k - 1 is a prime.at n=12A367478
• a(n) = Sum_{1 <= x_1, x_2 <= n} sigma( n/gcd(x_1, x_2, n) ).at n=24A373129