27043

Properties

Appears in sequences

• Discriminants of imaginary quadratic fields with class number 19 (negated).at n=42A046016
• a(n) = prime(2*n*(n+1)+1).at n=38A078746
• Denominator of next-best approximation to harmonic numbers. a(n) = Denominator of (A055573(n)-1)th convergent of n-th harmonic number, Sum_{k=1..n} 1/k.at n=13A113124
• Primes of the form 10n^2 + 3.at n=17A201710
• Primes p such that p+2^4, p+2^6 and p+2^8 are all primes.at n=31A269257
• Partial sums of A299894.at n=38A299895
• The number of vertices on a vesica piscis formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.at n=14A341878
• Irregular triangle read by rows: T(n,k) is the number of inequivalent connected induced k-vertex subgraphs of the hypercube graph of dimension n >= 0, 1 <= k <= 2^n.at n=43A369605
• For a line L in the plane, let C(L) denote the number of prime points [k, prime(k)] on L, and let M(L) denote the maximum prime(k) for any of these points; a(n) = minimum M(L) over all lines with C(L) = n, or -1 if there is no such line.at n=43A376187
• Prime numbersat n=2965