login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A220476 Let a(0)=1. For n > 0, a(n) is the least integer greater than a(n-1) such that the polynomial 1/a(0) + x^1/a(1) +...+ x^n/a(n) has exactly n distinct real roots. 0
1, 2, 17, 495, 47208, 14600027, 14610226398, 47283768063238 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..7.

EXAMPLE

1+x/2 has 1 real root. Then a(2)=17 is the least value > 2 such that 1+x/2+x^2/a(2) has 2 distinct real roots.

CROSSREFS

Sequence in context: A015202 A308864 A217284 * A293178 A172341 A007759

Adjacent sequences:  A220473 A220474 A220475 * A220477 A220478 A220479

KEYWORD

nonn,more

AUTHOR

Benoit Cloitre, Dec 15 2012

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 21 14:49 EDT 2019. Contains 328301 sequences. (Running on oeis4.)