3669120

Appears in sequences

• Numbers k such that phi(prime(k) + 1) == 0 (mod k).at n=30A067732
• a(0) = 1, a(1) = 1, a(n) = n! + (n-2)! for n >= 2.at n=10A108217
• Triangle T(n,k), n >= 0, 0 <= k <= n, read by rows: Number T(n,k) of forests of labeled rooted trees on n or fewer nodes using a subset of labels 1..n and k edges.at n=49A144289
• Integers which can be partitioned into two distinct factorials. 0! and 1! are not considered distinct.at n=43A301523
• a(n) = (n - 1)! * sigma_2(n), where sigma_2(n) = sum of squares of divisors of n (A001157).at n=8A318250