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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A020215 Pseudoprimes to base 87. 1
86, 91, 133, 217, 247, 301, 385, 403, 473, 559, 589, 817, 1045, 1105, 1111, 1333, 1661, 1705, 1729, 2047, 2365, 2626, 2651, 2821, 3553, 3565, 3785, 3913, 4123, 4141, 4681, 5005, 5461, 5719, 6533, 6601, 7471, 7483, 7657, 8029, 8041, 8401, 8686, 8911, 9331 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 87^(n-1) == 1 (mod n).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Index entries for sequences related to pseudoprimes

MATHEMATICA

base = 87; t = {}; n = 1; While[Length[t] < 100, n++; If[! PrimeQ[n] && PowerMod[base, n-1, n] == 1, AppendTo[t, n]]]; t (* T. D. Noe, Feb 21 2012 *)

CROSSREFS

Cf. A001567 (pseudoprimes to base 2).

Sequence in context: A259084 A058907 A045101 * A094776 A095595 A095581

Adjacent sequences:  A020212 A020213 A020214 * A020216 A020217 A020218

KEYWORD

nonn

AUTHOR

David W. Wilson

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 December 7 03:00 EST 2019. Contains 329836 sequences. (Running on oeis4.)