63744

Appears in sequences

• Expansion of 1/(1+2*x^2-2*x^3).at n=24A077964
• Expansion of 1/(1+2*x^2+2*x^3).at n=24A077968
• Expansion of x^3 / ( 1+2*x^2+2*x^3 ).at n=26A123958
• a(n) = A130179(n)/81.at n=36A130085
• Number of 4-step one or two space at a time rook's tours on an n X n board summed over all starting positions.at n=14A187289
• Arises in enumerating Huffman codes, compact trees, and sums of unit fractions.at n=18A194630
• Number of n X n 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal.at n=3A232369
• Number of nX4 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal.at n=3A232372
• T(n,k)=Number of nXk 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal.at n=24A232376
• Number of 4Xn 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal.at n=3A232379
• 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 502", based on the 5-celled von Neumann neighborhood.at n=16A288767
• a(n) = a(n-1) + a(n-2) + 2 a([n/2]), where a(0) = 1, a(1) = 2, a(2) = 3.at n=19A298347
• Numbers k such that s(k) = s(k+1), where s(k) is A059975.at n=27A327250
• Number of subsets of {1..n} such that it is not possible to choose a different prime factor of each element.at n=16A370583
• Number of subsets of {1..n} containing n such that it is not possible to choose a different prime factor of each element (non-choosable).at n=17A370587
• Expansion of (Sum_{k>=0} binomial(3*k,k) * x^k)^4.at n=5A378504