118949

Appears in sequences

• Numbers k such that 9*R_(k+2) - 4*10^k is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=24A257039
• Array read by antidiagonals: T(n,k) is the number of nonisomorphic multisets of endofunctions on an n-set with k endofunctions.at n=32A362897
• Number of nonisomorphic unordered triples of endofunctions on an n-set.at n=4A362898