172186884

Appears in sequences

• Generalized Euler phi function (for p=3).at n=17A003474
• Expansion of (1+x)/(1-3*x).at n=17A003946
• a(1)=1, a(2)=2, a(n) = 4*3^(n-3) for n >= 3.at n=18A025579
• a(n) = Sum_{k=0..m} (k+1) * A026120(n, m-k), where m=0 for n=0,1; m=n for n >= 2.at n=17A027327
• Number of compositions of n into 2*j-1 kinds of j's for all j>=1.at n=18A052156
• Number of n-step walks (each step +-1 starting from 0) which are never more than 2 or less than -2.at n=34A068911
• Determinant of the Cayley addition table of Z_{n}.at n=8A070896
• a(2n+1) = 3^n, a(2n) = 4*3^(n-1) except for a(0) = 1.at n=34A074324
• a(n) = n^(n-2) * binomial(n,2).at n=9A081131
• 9th binomial transform of (0,0,1,0,0,0,...).at n=9A081139
• Triangle, read by rows, resulting from the matrix product of triangle A108267 with Pascal's triangle (A007318).at n=37A108291
• a(n) = (7*3^n - (-3)^n)/6.at n=17A133125
• Spiral tiling numbers.at n=30A137333
• A triangular sequence from the Z/nZ matrix addition tables as in sequence A095897 as coefficients of characteristic polynomials: M(n,m)=Mod[n + m, d] for n <=m<=d.at n=45A138064
• Number of zig-zag paths from top to bottom of a rectangle of width 5 with n rows whose color is that of the top right corner.at n=33A153339
• a(n) = 3*a(n-2) for n > 2; a(1) = 4, a(2) = 3.at n=32A162766
• a(n) = 3*a(n-2) for n > 2; a(1) = 1; a(2) = 4.at n=33A166552
• Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^18 = I.at n=17A168729
• Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^19 = I.at n=17A168777
• Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^20 = I.at n=17A168825