57395628

Appears in sequences

• Expansion of (1+x)/(1-3*x).at n=16A003946
• a(1)=1, a(2)=2, a(n) = 4*3^(n-3) for n >= 3.at n=17A025579
• 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=16A027327
• Dan numbers: numbers m of the form 2^j * 3^k such that m +- 1 are twin primes.at n=14A027856
• Number of compositions of n into 2*j-1 kinds of j's for all j>=1.at n=17A052156
• Duplicate of A027856.at n=14A059961
• Number of n-step walks (each step +-1 starting from 0) which are never more than 2 or less than -2.at n=32A068911
• a(2n+1) = 3^n, a(2n) = 4*3^(n-1) except for a(0) = 1.at n=32A074324
• A133566 * A000244.at n=16A133647
• 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=31A153339
• a(n) = 3*a(n-2) for n > 2; a(1) = 4, a(2) = 3.at n=30A162766
• a(n) = 3*a(n-2) for n > 2; a(1) = 1; a(2) = 4.at n=31A166552
• Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^17 = I.at n=16A168681
• 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=16A168729
• 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=16A168777
• 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=16A168825
• Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^21 = I.at n=16A168873
• Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^22 = I.at n=16A168921
• Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^23 = I.at n=16A168969
• Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^24 = I.at n=16A169017