21738

Appears in sequences

• Numbers k such that 5*2^k - 1 is prime.at n=30A001770
• Sum of 12 positive 9th powers.at n=17A004801
• a(n) is the maximal row sum in the character table of the symmetric group S_n.at n=12A085547
• G.f.: A(x) = Product_{n>=1} 1/(1 - A007947(n)*x^n)^(1/n), where A007947(n) is the product of the distinct prime factors of n.at n=26A094947
• Define k(0) = 2 and k(m) = m^2-k(m-1) for m >= 1. This is a list of those terms k(m) for which k(m)+1 and k(m)-1 are both in A008578 (primes including 1).at n=7A154734
• Numbers k such that 2^k + 25 is prime.at n=30A157006
• Total sum of the 9th powers of lengths of ascending runs in all permutations of [n].at n=3A228999
• Number of length 3+3 0..n arrays with every four consecutive terms having the sum of some three elements equal to three times the fourth.at n=16A248540
• Number of (not necessarily maximal) cliques in the n-polygon diagonal intersection graph.at n=19A300524
• a(n) = 9*n^2 + 21*n - 6 (n>=1).at n=47A304374
• Ulam numbers sandwiched between twin prime numbers.at n=34A380429