797162

Appears in sequences

• a(n) = (3^n + 1)/2.at n=13A007051
• Number of periodic palindromic structures of length n using a maximum of three different symbols.at n=27A056504
• Number of set partitions with at most 3 blocks; number of Dyck paths of height at most 4; dimension of space of symmetric polynomials in 3 noncommuting variables.at n=14A124302
• a(n) = 3*a(n-1) - a(n-3) + 3*a(n-4), with initial values 2,5,13,40.at n=12A133448
• a(n) = 3*a(n-1) - a(n-3) + 3*a(n-4), with initial values 2,4,13,40.at n=12A133453
• a(n) = 4*a(n-1) - 7*a(n-2) + 6*a(n-3) - 3*a(n-4), starting with 0, 1, 2, 3.at n=26A134581
• a(0)=1; a(3n+1) = a(3n)+1, a(3n+2) = a(3n+1) + a(3n) (=3*A000244), a(3n+3) = a(3n+2) + a(3n) (=A003462(n+2)).at n=37A140298
• a(0) = 1 and a(n) = (3^n - (-1)^n)/2 for n >= 1.at n=13A152011
• a(n) = (3*9^n + 1)/2.at n=6A199560
• T(n,k)=Number of nXk 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.at n=34A208392
• Number of 7Xn 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.at n=1A208398
• T(n,k)=Number of nXk 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 in row major order.at n=34A233082
• Number of 7Xn 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 in row major order.at n=1A233088
• Permutation of natural numbers, the even bisection of A241909 incremented by one and halved; equally, a composition of A241909 and A048673: a(n) = A048673(A241909(n)).at n=40A243066
• Permutation of natural numbers: a(n) = A048673(A122111(n)).at n=40A243506
• a(1) = 1, then A007051 ((3^n)+1)/2 interleaved with A057198 (5*3^(n-1)+1)/2.at n=25A246360
• E.g.f.: S(x,y) = (sinh(x) + sinh(y)) / (1 - sinh(x)*sinh(y)), where S(x,y) = Sum_{n>=0} Sum_{k=0..2*n+1} T(n,k) * x^(2*n+1-k)*y^k/((2*n+1-k)!*k!), as a triangle of coefficients T(n,k) read by rows.at n=58A322194
• E.g.f.: S(x,y) = (sinh(x) + sinh(y)) / (1 - sinh(x)*sinh(y)), where S(x,y) = Sum_{n>=0} Sum_{k=0..2*n+1} T(n,k) * x^(2*n+1-k)*y^k/((2*n+1-k)!*k!), as a triangle of coefficients T(n,k) read by rows.at n=69A322194
• a(n) = (-1)^(n+1) * (3^n+1)/2.at n=13A341463
• Cogrowth sequence of the 18-element group S3 X C3 = <S,T,U | S^3, T^2, U^3, (ST)^2, [S,U], [T,U]>.at n=15A378109