29821

Appears in sequences

• Number of switching networks under action of AG_n(Z_2) acting on 2 variables.at n=3A000820
• Integers k such that A166100(k)/A005408(k) is not an integer.at n=38A166101
• Number of steps to reach 1 in '3x+1' (or Collatz) problem starting with the n-th Mersenne prime.at n=15A181777
• a(n) = (2*n^3 + 3*n^2 + n + 3)/3.at n=35A188475
• Centered 12-gonal numbers which are semiprimes, intersection of A003154 and A001358.at n=31A218172
• Expansion of (1 + 6*x + x^2 + 12*x^3 - 2*x^4)/((1 - x)^4*(1 + x)^3).at n=42A268579
• Number of 5-regular polyhedra with 2n nodes.at n=9A308489
• a(n) is the number of partitions of 72*n + 42 into 10 odd squares.at n=46A323891
• a(n) = Sum_{k=1..n} gcd(k, n)^3.at n=30A343497
• Distance from 10^n to the next prime triplet.at n=43A357052
• a(n) is the number of distinct scalar products which can be formed by pairs of signed permutations (V, W) of [n].at n=35A358655