# Number sequence 15, 101, 8, 86, 9699 ...

by shroo
Tags: 9699, number, sequence
 P: 688 I used linear regression to produce$$x_n = \frac{ -2009823672425 x_{n-1}^2 + 1317576645654994 x_{n-2}^2 + 19713318671536597 x_{n-1} - 131718609410997380 x_{n-2} - 290871998770928574} {43322484909156}$$though, even if it is a perfect fit, it's probably not what the puzzle designer had in mind, as the next value is$$\frac {10226107345860276146148} {3610207075763}$$and the rest plunge down the negative.