login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A248352 Numbers k such that 10^k - 987654321 is prime. 3
986, 1240, 1928, 4054, 14252, 47528, 101728 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Note that 987654321 is the largest pandigital number in base-10, omitting 0.

LINKS

Table of n, a(n) for n=1..7.

MATHEMATICA

Select[Range[10000], PrimeQ[10^# - 987654321] &] (* Robert Price, Dec 05 2019 *)

PROG

(PARI) for(n=1, 10^4, if(ispseudoprime(10^n-987654321), print1(n, ", ")))

CROSSREFS

Cf. A248349, A248350, A248351, A050289.

Sequence in context: A183718 A163025 A069299 * A072316 A222351 A221696

Adjacent sequences:  A248349 A248350 A248351 * A248353 A248354 A248355

KEYWORD

nonn,hard,more

AUTHOR

Derek Orr, Oct 05 2014

EXTENSIONS

a(6)-a(7) from Robert Price, Dec 05 2019

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 6 23:36 EDT 2022. Contains 357270 sequences. (Running on oeis4.)