33621

Appears in sequences

• Number of minimal 3-covers of a labeled n-set.at n=4A003468
• Least m such that if r and s in {1/1, 1/4, 1/9,..., 1/n^2} satisfy r < s, then r < k/m < s for some integer k.at n=44A024827
• Duplicate of A003468.at n=4A028109
• Triangle of a(n,k) = number of k-member minimal covers of an n-set (n >= k >= 1).at n=23A035348
• Triangle of Lehmer-Comtet numbers of 2nd kind.at n=31A039621
• a(n) = Sum_{k=1..n} lcm(k,n)/gcd(k,n).at n=40A056789
• Smallest integer > 1 which is both n-gonal and centered n-gonal.at n=38A072277
• Sum of terms in row n of A081520.at n=40A081519
• 4-Stirling numbers of the second kind.at n=31A143496
• a(n) = 20*n^2 + 1.at n=41A158493
• a(n) = n*(n^2 - 4*n + 5)/2.at n=42A162607
• Numbers n such that n!! - 2^8 is prime.at n=26A265114
• a(n) = (n^n - 3*(n-1)^n + 3*(n-2)^n - (n-3)^n)/6.at n=7A281595
• a(0) = a(1) = a(2) = 1; a(n) = a(n-3) + Sum_{k=0..n-4} a(k) * a(n-k-4).at n=24A343304
• Triangle read by rows. The Bell transform of the sequence {m^m | m >= 0}.at n=40A354794