27050

Appears in sequences

• Numbers k such that sigma(k) mod pi(k) = 1.at n=18A073723
• a(n) = n*(6*n^2 + 15*n + 5)/2.at n=20A163833
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 347", based on the 5-celled von Neumann neighborhood.at n=33A271299
• Number of integer partitions of n containing all of their distinct multiplicities.at n=47A325705
• a(0) = 1; a(n) = (1/n) * Sum_{k=2..n} (binomial(n,k) * k!)^2 * a(n-k) / k.at n=6A346291
• Triangle read by rows, with T(n,k) giving the number of n X n Boolean matrices with exactly k ones that have no zero rows and at least one zero column.at n=40A392482