21846

Appears in sequences

• Numbers k such that x^k + x + 1 is irreducible over GF(2).at n=30A002475
• a(2*n) = 2*a(2*n-1), a(2*n+1) = 2*a(2*n)-1.at n=16A005578
• a(n) = a(n-1) + 2*a(n-2) with a(0)=0, a(1)=2.at n=15A014113
• Numbers k such that k | 8^k + 8.at n=25A015897
• Number of steps from one unit vector to next in linear quantum cellular automata.at n=13A019543
• a(n) = C(n,2) + C(n,5) + ... + C(n, 3*floor(n/3)+2).at n=16A024495
• a(n) = Sum_{k=0..n} (k+1) * A026703(n, k).at n=10A027256
• Expansion of sum ( q^n / product( 1-q^k, k=1..5*n), n=0..inf ).at n=31A035297
• Numbers whose base-2 representation has exactly 14 runs.at n=8A043581
• Array A read by diagonals; n-th difference of (A(k,n), A(k,n-1),..., A(k,0)) is (k+2)^(n-1), for n=1,2,3,...; k=0,1,2,...at n=46A047848
• a(n) = (4^n + 2)/3.at n=8A047849
• Expansion of 2*(1-x-x^2)/((1-x)*(1+x)*(1-2*x)).at n=15A052953
• Prime factorization of n encoded with the run lengths of binary expansion + 1.at n=46A075160
• Expansion of (1 - x)/((1 + x)*(1 - 2*x)).at n=16A078008
• Expansion of (1-x)/(1+x+2*x^2+2*x^3).at n=32A078052
• a(n)*a(n+3) - a(n+1)*a(n+2) = 2^n, given a(0)=1, a(1)=2, a(2)=2.at n=16A080880
• a(n) = 2^n - A081374(n).at n=14A083322
• Binomial transform of (-1)^mod(n,3) (A257075).at n=16A086953
• Generalized multiplicative Jacobsthal sequence.at n=16A087464
• Numbers of the form (4^n + 4^(n-1) + ... + 1) + (n mod 2).at n=6A088556