A143849 Let x(1) = 1 and x(n) = x(n-1)^2 + i for n>1; a(n) is the imaginary part of x(n).

0, 1, 3, 1, -17, -2719, -33231617, -1990664248298239, 825155821714086784897292716543, -6468873315977272230111786035347284128217298704834756326835199

Offset

1,3

Links

Table of n, a(n) for n=1..10.

Formula

a(n+1) = 2*a(n)*A143848(n) + 1.

Example

The x(n) sequence starts 1, 1+i, 3*i, -9+i, 80-17*i, 6111-2719*i, ...

Crossrefs

A143848 gives the read part of x(n).

Sequence in context: A151918 A089974 A346039 * A380013 A370233 A335689

Adjacent sequences: A143846 A143847 A143848 * A143850 A143851 A143852

Keyword

sign

Author

Reinhard Zumkeller, Sep 03 2008

Extensions

Definition clarified by N. J. A. Sloane, Jul 11 2024 at the suggestion of Harvey P. Dale.

Status

approved