25531

Appears in sequences

• a(n) = 5*a(n-2) - 2*a(n-4), with initial terms 0,1,1,3.at n=15A005824
• Number of independent vertex sets of the n X n torus grid graph.at n=4A027683
• a(n) = Sum_{i=0..floor(n/2)} T(2i,n-2i), array T as in A049735.at n=28A049738
• a(n) = 5*a(n-1) - 2*a(n-2) for n>1, with a(0) = 1, a(1) = 3.at n=7A052984
• Number of binary arrangements without adjacent 1's on n X n torus connected ne-sw nw-se.at n=4A067960
• Triangle T(n,k) read by rows: number of k X k triangular (0,1)-matrices with exactly n entries equal to 1 and no zero rows or columns.at n=62A137252
• a(n) = -5*a(n-1)-2*a(n-2), n>1 ; a(0)=1, a(1)=-1 .at n=8A152594
• Number of independent sets of nodes in C_5 X C_n (n >= 1).at n=5A182041
• Number of partitions of n into lower Wythoff numbers (A000201).at n=58A192184
• Number of partitions p of n such that max(p) - (number of parts of p) is a part of p.at n=47A238544
• The 240-degree spoke (or ray) of a hexagonal spiral of Ulam.at n=46A244805
• List of quadruples (r,s,t,u): the matrix M = [[9,24,16][3,10,8][1,4,4]] is raised to successive powers, then (r,s,t,u) are the square roots of M[3,1], M[3,3], M[1,1], M[1,3] respectively.at n=30A249581
• Expansion of Product_{k>=1} 1/(1 - (5*k-2)*x^(5*k-2)).at n=31A265832
• 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 478", based on the 5-celled von Neumann neighborhood.at n=14A282484
• Number of polygons formed when every pair of vertices of a regular n-gon are joined by an infinite line.at n=22A344857
• Number of polygons formed when every pair of vertices of a regular (2n-1)-gon are joined by an infinite line.at n=11A344866
• Numbers whose prime factorization (prime factors and exponents) contains the digits 1 and 2 at least once, but no other digits.at n=29A364484