4192256

Appears in sequences

• Expansion of g.f.: 2*x*(1-x)/((1-2*x)*(1-2*x^2)).at n=22A014236
• a(n) = 4^n - 2^n.at n=11A020522
• Number of reversible strings with n beads of 2 colors. If more than 1 bead, not palindromic.at n=22A032085
• Sum of every 4th entry of row n in Pascal's triangle, starting at binomial(n,2).at n=24A038505
• Number of elements of GF(2^n) with trace 0 and subtrace 0.at n=24A038518
• Number of 2n-bead balanced binary necklaces which are equivalent to their reversed complement, but not equivalent to their reverse and complement.at n=23A045678
• Number of 2n-bead balanced binary necklaces of fundamental period 2n which are equivalent to their reversed complement, but are not equivalent to their reverse and complement.at n=23A045687
• Number of compositions of n with an odd number of 1's.at n=23A113980
• G.f.: 1/((1-2*x)*(1-2*x^2)).at n=21A122746
• a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) for n >= 4 starting with a(0) = 1, a(1) = 2, a(2) = 4, and a(3) = 6.at n=23A131885
• Denominator of ez(n-1)*n!/(4^n-2^n) where ez(n) is the n-th coefficient of sec(t)+tan(t) for n>0, a(0) = 1.at n=11A193473
• a(n) = 4*16^n - 2*4^n.at n=5A193475
• The denominators of the Bernoulli secant numbers at odd indices.at n=5A193476
• The number of length n binary words with some prefix which contains two more 1's than 0's or two more 0's than 1's.at n=22A233411
• Number of length n+2 0..1 arrays with the sum of the maximum minus twice the median plus the minimum of adjacent triples multiplied by some arrangement of +-1 equal to zero.at n=20A251421
• Number of binary strings of length n having the maximum possible number of different antipower periods.at n=21A274409
• Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 213", based on the 5-celled von Neumann neighborhood.at n=21A279879
• Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 469", based on the 5-celled von Neumann neighborhood.at n=21A282417
• Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 54", based on the 5-celled von Neumann neighborhood.at n=22A285611
• Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 107", based on the 5-celled von Neumann neighborhood.at n=22A285835