2033628

Appears in sequences

• Tetranacci numbers: a(n) = a(n-1) + a(n-2) + a(n-3) + a(n-4) for n >= 4 with a(0) = a(1) = a(2) = 0 and a(3) = 1.at n=26A000078
• a(n)=the sum of the (1,2)- and (1,3)-entries and twice the (1,4)-entry of the matrix P^n + T^n, where the 4 X 4 matrices P and T are defined by P=[0,1,0,0;0,0,1,0;0,0,0,1;1,0,0,0] and T=[0,1,0,0;0,0,1,0;0,0,0,1;1,1,1,1].at n=24A109525
• Number of sequences of length n with elements {-2,-1,+1,+2}, counted up to simultaneous reversal and negation, such that the sum of elements of the whole sequence but of no proper subsequence equals 0 modulo n. For n>=4, the number of Hamiltonian (undirected) cycles on the circulant graph C_n(1,2).at n=37A137726
• Expansion of (3-2*x)/(1-x-x^3)+x/(1-x)^2+x/(1-x^2).at n=38A226509
• Number of (undirected) Hamiltonian cycles in the n-antiprism graph.at n=18A306447
• Number of compositions (ordered partitions) of n into parts not greater than sqrt(n).at n=23A364526