203450521

Appears in sequences

• a(n) = (1 - (-5)^n)/6.at n=12A014986
• Gaussian binomial coefficient [ n,12 ] for q=-5.at n=1A015427
• Linear 2nd order recurrence: a(n) = 4*a(n-1) + 5*a(n-2).at n=13A015531
• Cyclotomic polynomials at x=-5.at n=13A020504
• Zsigmondy numbers for a = 5, b = 1: Zs(n, 5, 1) is the greatest divisor of 5^n - 1^n (A024049) that is relatively prime to 5^m - 1^m for all positive integers m < n.at n=25A064081
• a(n) = (5*5^n + (-1)^n)/6.at n=12A083425
• Expansion of (1-4*x-x^2)/((1-x)*(1-4*x-5*x^2)).at n=13A100284
• Least k for which Omega(6k-1) + Omega(6k+1) >= n.at n=16A145194
• Least k for which Omega(6k-1) + Omega(6k+1) >= n.at n=17A145194
• a(n) = Sum_{j=0..12} (-n)^j.at n=5A266229
• a(n) = p(0,n), where p(x,n) is the strong divisibility sequence of polynomials based on sqrt(5) as in A327322.at n=12A329011