-5983

Appears in sequences

• a(n) = a(n-1) - 2*a(n-2) with a(0) = 2, a(1) = 1.at n=24A002249
• Let phi = arccos(1/3), the dihedral angle of the regular tetrahedron. Then cos(n*phi) = a(n)/3^n.at n=8A025172
• Expansion of (1 - x)/(1 - 2*x + 3*x^2) in powers of x.at n=16A087455
• Expansion of (1-4x^2)/(1+3x+4x^2).at n=12A128415
• A nonsense sequence.at n=26A143044
• Expansion of (2 + x + x^2 + x^3 - x^4 - 2*x^5 - 4*x^6 - 8*x^7) / (1 - x^4 + 16*x^8) in powers of x.at n=24A247487
• a(n) = 3*a(n-1) - 4*a(n-2) with a(0) = 2, a(1) = 3.at n=12A247563
• a(n) = 3*a(n-2) - 4*a(n-4) with a(0) = 2, a(1) = 1, a(2) = 3, a(3) = 1.at n=24A247564
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 81", based on the 5-celled von Neumann neighborhood.at n=41A270101
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 337", based on the 5-celled von Neumann neighborhood.at n=41A271288
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of (1+(k-1)*x) / (1+2*(k-1)*x+((k+1)*x)^2).at n=63A333989