69273668

Appears in sequences

• Number of n-bead necklaces with 2 colors when turning over is not allowed; also number of output sequences from a simple n-stage cycling shift register; also number of binary irreducible polynomials whose degree divides n.at n=31A000031
• a(n) is the n-th term in sequence A_n, respecting the offset, or a(n) = -1 if A_n has fewer than n terms.at n=30A051070
• Number of subsets of {1,2,...,n} which sum to 0 modulo n.at n=30A063776
• a(n) = (1/n) * Sum_{d divides n} (-1)^(n+d)*phi(n/d)*2^d.at n=30A074763
• Bisection of A000031.at n=15A100447
• a(n) = A159553(n)/n.at n=30A159554
• Number of binary strings of length n that are "prefix heavy", meaning that the fraction of "1" bits in any nonempty prefix is at least as great as the fraction of "1" bits in the entire string.at n=31A298072
• a(n) = ceiling((2^n+n-1)/n).at n=30A373895