70981

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 35.at n=6A031623
• a(0)=1, a(1)=1, a(2)=1, a(n) = 2*a(n-1) + a(n-2) + 1.at n=14A033539
• Primes in A005891 = Centered pentagonal numbers: (5n^2 + 5n + 2)/2.at n=28A145838
• Primes whose base-4 representation also is the base 2-representation of a prime.at n=27A235461
• Numbers n such that (n, sigma(n), tau(n)) lies on a sphere with integral radius centered at the origin, i.e., n^2 + sigma(n)^2 + tau(n)^2 is a square.at n=6A243455
• Centered 13-gonal (or tridecagonal) primes.at n=22A262493
• Half of the height of the right trapezoidal gnomon (of the derivative of Y=X^5).at n=12A281999
• Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 534", based on the 5-celled von Neumann neighborhood.at n=16A282960
• Expansion of (1 + 3*x - 2*x^2)/(1 - 7*x + 7*x^2 - x^3).at n=6A301383
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = n! * Sum_{j=0..n} binomial(n+(k-1)*(j+1),n-j)/j!.at n=50A361616
• E.g.f. satisfies A(x) = exp( x/(1-x)^2 * A(x)^2 ).at n=5A362776
• Prime numbersat n=7030