1162241784

Appears in sequences

• a(n) = (3^n + 2*3^(n/2)*cos(n*Pi/6))/3.at n=20A092236
• Expansion of x^2*(1-x)/((1-3*x)*(1-3*x^2)).at n=20A122006
• Expansion of 2*x^2*(1-2*x) / ((3*x-1)*(3*x^2-1)).at n=20A122007
• Binomial transform of A131666.at n=21A135254
• a(n) = 3^(n-1)*(3^n - 1), n >= 0.at n=10A219205
• a(1) = 2, a(2) = 4, a(3) = 6; for n > 3, a(n) = 3*a(n-1) - 3*a(n-2) + 9*a(n-3).at n=19A318609
• a(1) = 0, a(2) = 4, a(3) = 12; for n > 3, a(n) = 3*a(n-1) - 3*a(n-2) + 9*a(n-3).at n=19A318610
• a(n) is the number of words of length n on the alphabet {0,1,2} with the number of 0's plus the number of 1's congruent to the number of 2's modulo 3.at n=20A334656