268419060

Appears in sequences

• Number of aperiodic binary strings of length n; also number of binary sequences with primitive period n.at n=28A027375
• Row sums of triangle T(m,n) = number of solutions to 1 <= a(1) < a(2) < ... < a(m) <= n, where gcd(a(1), a(2), ..., a(m), n) = 1, in A020921.at n=27A038199
• Number of 4-ary sequences with primitive period n.at n=14A054719
• Number of primitive (aperiodic) words of length n which contain exactly two different symbols.at n=27A056267
• Number of primitive (aperiodic) palindromes using a maximum of four different symbols.at n=27A056460
• Number of 3 X n binary matrices that are "primitive"; that is, they cannot be expressed as a "tiling" by a smaller matrix.at n=6A290754