1081365

Appears in sequences

• Define a sequence of fractions by x(m+1) = (x(m)^2+x(m)-1)/(x(m)+1) with x(0)=1; sequence gives values of k such that sgn(x(k))<>sgn(x(k-1)).at n=39A064690
• Short leg A of primitive Pythagorean triangles such that perimeters and products of 3 sides are Averages of twin prime pairs, q=p+1, a=q^2-p^2, c=q^2+p^2, b=2*p*q, ar=a*b/2; s=a+b+c, s-+1 are primes, pr=a*b*c, pr-+1 are primes.at n=28A155180