70949

Properties

Appears in sequences

• a(0) = 1, a(n) is the greatest prime factor of a(n-1)^2+1 for n > 0.at n=11A031439
• Primes from merging of 5 successive digits in decimal expansion of the Euler-Mascheroni Constant.at n=19A104939
• Triangle read by rows: T(n,k) is the number of deco polyominoes of height n such that the bottom of the last column is at level k (n>=1; k>=0). A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.at n=41A121632
• Primes from merging of 5 successive digits in decimal expansion of Euler-Mascheroni constant.at n=20A198779
• a(n) is the first emirp that starts a chain of exactly n emirps under the mapping f(x) = x + reverse(x) + 1.at n=2A345217
• Triangle read by rows: numerators of the almost-Riordan array ( (3*x - 2 - 2*sqrt(1 - x))/(-x^2 + 5*x - 2 + 2*(x - 1)*sqrt(1 - x)) | 4/(2*(1 - x)*sqrt(1 - x) + x^2 - 5*x + 2), (8 - 4*x - 8*sqrt(1 - x))/x ).at n=48A389710
• Prime numbersat n=7025