190513

Appears in sequences

• Expansion of x/(1 - 4*x - 3*x^2).at n=9A015530
• Strong pseudoprimes to base 83.at n=34A020309
• Greatest number having exactly n representations as ab+ac+bc with 0 < a < b < c.at n=44A094377
• Numbers with sum of digits = 19, divisible by 19 and containing the string "19".at n=22A121669
• Number of (w,x,y,z) with all terms in {1,...,n} and 3w<x+y+z+n.at n=22A212249
• Numerator of Sum_{k=1..n-1} 1/(k*(n-k))^2.at n=8A304581
• Odd numbers k > 1 such that gcd(5,k) = 1 and 5^((k-1)/2) == -(5/k) (mod k), where (5/k) is the Jacobi symbol (or Kronecker symbol); Euler pseudoprimes to base 5 (A262052) that are not Euler-Jacobi pseudoprimes to base 5 (A375914).at n=15A375816