193710244

Appears in sequences

• a(n) = (3^n - 1)/2.at n=18A003462
• Degree of variety K_{2,n}^5.at n=3A013702
• Numbers that are repdigits in base 3.at n=35A048328
• a(n) = a(n-1) + 3*a(n-2) - 3*a(n-3), with a(0)=a(1)=1, a(2)=4.at n=34A052993
• Number of primitive (aperiodic) word structures of length n using a 3-ary alphabet.at n=18A056274
• Number of primitive (aperiodic) palindromic structures using a maximum of three different symbols.at n=37A056477
• Number of primitive (period n) periodic palindromic structures using a maximum of three different symbols.at n=37A056514
• a(n) = floor(n^n/2).at n=9A057065
• a(n) = floor(9^9/n).at n=1A057071
• Table read by antidiagonals of T(n,k)=floor(n^n/k) with n,k >= 1.at n=53A057075
• a(n) = (-1)^n * (3^n - 1)/2.at n=18A076040
• Square array read by antidiagonals: degree of the K(2,p)^q variety.at n=41A082635
• Expansion of (1+3x)/((1-x^2)(1-3x^2)).at n=34A094025
• An inverse Catalan transform of A003462.at n=36A106233
• Expansion of x*(1+x+2*x^3) / ((x-1)*(1+x)*(3*x^2-1)).at n=35A120463
• a(n) = 3*a(n-1) - a(n-3) + 3*a(n-4), with initial values 1,4,14,41.at n=17A132357
• a(0) = 1 and a(n) = (3^n - (-1)^n)/2 for n >= 1.at n=18A152011
• Number of compositions of odd natural numbers into 9 parts <= n.at n=8A191680
• a(n) = (9^n - 1)/2.at n=9A191681
• Number of compositions of odd natural numbers into 6 parts <= n.at n=26A191901