1290555
domain: N
Appears in sequences
- Number of n-bead necklaces with beads of 2 colors and primitive period n, when turning over is not allowed but the two colors can be interchanged.at n=26A000048
- a(n) = floor(2^(n-1)/n).at n=25A006788
- Number of binary vectors (x_1,...x_n) satisfying Sum_{i=1..n} i*x_i = 3 (mod n+1) = size of Varshamov-Tenengolts code VT_3(n).at n=25A054200
- Nearest integer to 2^(n-1)/n.at n=25A054650
- Number of monic irreducible polynomials over GF(4) of degree n with fixed nonzero trace.at n=12A054660
- Number of monic irreducible polynomials over GF(4) with zero trace.at n=12A054661
- Number of 4-ary Lyndon words of length n with trace 0 mod 4.at n=12A054664
- Number of primitive (period n) n-bead necklace structures using exactly two different colored beads.at n=25A056303
- a(n) = floor(8^8/n).at n=12A057070
- Duplicate of A054661.at n=12A074024
- Fermat quotients for base 4: (4^(p - 1) - 1)/p, where p = prime(n).at n=4A180511
- Number of nonzero elements in GF(2^n) that are 13th powers.at n=23A213248
- Positive integers with the property that if the base-4 representation is reversed the result is three times the original number.at n=12A223078
- Number of nX2 0..3 arrays with no element equal to two plus the sum of elements to its left or two plus the sum of elements above it or two plus the sum of the elements diagonally to its northwest, modulo 4.at n=9A240418