33747840

Appears in sequences

• Numbers n = concat(s,t) such that n = sigma(s*t), where sigma(x) is the sum of the divisors of x.at n=16A260097
• Triangle read by rows: T(n,m) = one-half of number of embeddings of the n-wheel with k = n+1-2m regions (n >= 1, 0 <= m <= floor(n/2)).at n=34A301731
• a(n) = n! - 2(n-1)! + 3(n-2)!.at n=9A374649