86464

Appears in sequences

• From a counter moving problem.at n=21A004138
• a(0) = a(1) = 1; a(n+2) = 2*a(n+1) + 2*a(n).at n=12A026150
• Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 21.at n=13A031699
• a(n)*a(n+3) - a(n+1)*a(n+2) = 2^n, given a(0) = 1, a(1) = 1, and a(2) = 1.at n=14A080876
• a(n) = 8*a(n-1) - 4*a(n-2), where a(0) = 1, a(1) = 4.at n=6A090965
• Least number 2k such that p^3 divides the numerator of the Bernoulli number B(2k), where p is the n-th irregular prime, A000928(n).at n=1A092682
• a(n) = 441n^2 + 2n.at n=13A158321
• Expansion of g.f.: x^2*(1 + x - x^2)/(1 - 2*x^2 - 2*x^4).at n=25A160444
• Elements of A160444, pairs of consecutive entries swapped.at n=24A160572
• Least even integer k such that numerator(B_k) == 0 (mod 59^n).at n=2A299466
• Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero.at n=7A306049
• E.g.f.: Sum_{n>=0} ((1+x)^n - 1)^n * 4^n / n!.at n=4A326274
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of (1-(k+1)*x) / (1-2*(k+1)*x+((k-1)*x)^2).at n=51A333988
• a(n) = Sum_{k=0..floor(n/3)} 2^k * 3^(n-3*k) * binomial(k,n-3*k)^2.at n=18A387479