43690

Appears in sequences

• a(2n) = 2*a(2n-1), a(2n+1) = 2*a(2n)+1 (also a(n) is the n-th number without consecutive equal binary digits).at n=16A000975
• Barlow packings with group R3(bar)m(SO) that repeat after 6n+3 layers.at n=16A011954
• a(n) = a(n-1) + 2*a(n-2) with a(0)=0, a(1)=2.at n=16A014113
• a(n) = (2/3)*(4^n-1).at n=8A020988
• a(n) = C(n,1) + C(n,4) + ... + C(n, 3*floor(n/3) + 1).at n=16A024494
• a(n) = a(n-1) + 2*a(n-2) + 2, for n>=3, where a(0)= 1, a(1)= 2, a(2)= 4.at n=15A026644
• Numbers n such that number of runs in the base 4 representation of n is congruent to 1 mod 8.at n=22A043851
• Numbers n such that number of runs in the base 4 representation of n is congruent to 1 mod 9.at n=22A043859
• Numbers n such that number of runs in the base 4 representation of n is congruent to 1 mod 10.at n=22A043868
• Numbers that are repdigits in base 4.at n=23A048329
• Numerator of the expected time to finish a random Tower of Hanoi problem with n disks using optimal moves.at n=16A060590
• Number of 132 and 213-avoiding derangements of {1,2,...,n}.at n=17A061547
• Half totient of 2^n+1.at n=16A063474
• Positions of negative coefficients in cyclotomic polynomial Phi_n(x), converted from binary to decimal. (The constant term in the least significant bit (bit-0), the term x in the next bit (bit-1) and so on).at n=34A063698
• Solutions to phi(gpf(x)) - gpf(phi(x)) = 254 = c are special multiples of 257, x = 257k, where largest prime factors of factor k were observed from {2, 3, 5, 17}. See solutions to other even cases of c (=A070813): A007283 for 0, A070004 for 2, A070814 for 14, A070816 for 65534.at n=31A070815
• Prime factorization of n+1 encoded with the run lengths of binary expansion.at n=52A075158
• Sequence A075166 interpreted as binary numbers and converted to decimal.at n=18A075165
• List of codewords in binary lexicode with Hamming distance 8 written as decimal numbers.at n=23A075940
• Expansion of (1 - x)/((1 + x)*(1 - 2*x)).at n=17A078008
• Expansion of (1-x)/(1+x+2*x^2+2*x^3).at n=31A078052