1398101

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=21A000975
• Jacobsthal sequence (or Jacobsthal numbers): a(n) = a(n-1) + 2*a(n-2), with a(0) = 0, a(1) = 1; also a(n) = nearest integer to 2^n/3.at n=22A001045
• a(n) = (4^n - 1)/3.at n=11A002450
• Divisors of 2^22 - 1.at n=14A003531
• Indices of last windows of trapezoidal maps.at n=21A007873
• Cyclotomic polynomials at x=4.at n=11A019322
• Cyclotomic polynomials at x=-4.at n=22A020503
• 11th cyclotomic polynomial evaluated at powers of 2.at n=2A020519
• Gaussian binomial coefficients [ n,10 ] for q = 4.at n=1A022209
• a(n) = C(n,0) + C(n,3) + ... + C(n,3[n/3]).at n=22A024493
• a(n) = C(n,1) + C(n,4) + ... + C(n, 3*floor(n/3) + 1).at n=21A024494
• a(n) = Sum_{k=0..floor(n/2)} A026637(n, k).at n=21A026645
• Numbers that are repdigits in base 4.at n=31A048329
• Expansion of 1/((1 - x)*(1 - 2*x)*(1 + 2*x)).at n=21A052992
• Expansion of 1/((1 - x)*(1 - 2*x)*(1 + 2*x)).at n=20A052992
• a(n) = floor(8^8/n).at n=11A057070
• Number of points of period n under the dual of the map x->2x on Z[1/6].at n=21A059990
• a(n) = Sum_{j=0..10} n^j.at n=4A060885
• Zsigmondy numbers for a = 4, b = 1: Zs(n, 4, 1) is the greatest divisor of 4^n - 1^n (A024036) that is relatively prime to 4^m - 1^m for all positive integers m < n.at n=10A064080
• Sum of squares of divisors of square numbers.at n=31A065827