88574

Appears in sequences

• a(n) = (3^n + 1)/2.at n=11A007051
• Number of periodic palindromic structures of length n using a maximum of three different symbols.at n=23A056504
• 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=12A124302
• a(n) = ceiling(9^n/n).at n=5A129793
• a(n) = 3*a(n-1) - a(n-3) + 3*a(n-4), with initial values 1,4,14,41.at n=10A132357
• a(n) = 3*a(n-1) - a(n-3) + 3*a(n-4), with initial values 2,4,13,40.at n=10A133453
• 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=31A140298
• a(0) = 1 and a(n) = (3^n - (-1)^n)/2 for n >= 1.at n=11A152011
• a(n) = (3*9^n + 1)/2.at n=5A199560
• 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=26A208392
• Number of 6Xn 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=1A208397
• Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero with no three beads in a row equal.at n=39A208946
• 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=26A233082
• Number of 6Xn 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=1A233087
• 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=30A243066
• Permutation of natural numbers: a(n) = A048673(A122111(n)).at n=30A243506
• a(1) = 1, then A007051 ((3^n)+1)/2 interleaved with A057198 (5*3^(n-1)+1)/2.at n=21A246360
• Number of times that the numerator of a sum generated from the set 1, 1/2, 1/3,..., 1/n is a Fibonacci number.at n=33A256220
• E.g.f.: A(x,y) = (cosh(x)*cosh(y) + sinh(x) + sinh(y)) / (1 - sinh(x)*sinh(y)), where A(x,y) = Sum_{n>=0} Sum_{k>=0} T(n,k) * x^n*y^k/(n!*k!), as a square table of coefficients T(n,k) read by antidiagonals.at n=93A322190
• E.g.f.: A(x,y) = (cosh(x)*cosh(y) + sinh(x) + sinh(y)) / (1 - sinh(x)*sinh(y)), where A(x,y) = Sum_{n>=0} Sum_{k>=0} T(n,k) * x^n*y^k/(n!*k!), as a square table of coefficients T(n,k) read by antidiagonals.at n=102A322190