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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A090157 Primes of the form identical digits preceded by a 9. 1
97, 911, 977, 97777, 911111, 97777777777777777777, 911111111111111111111, 97777777777777777777777777777, 911111111111111111111111111111111111111111 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..21

MATHEMATICA

Select[ FromDigits /@ Flatten[ Table[ PadRight[{9}, i, # ] & /@ {1, 2, 3, 4, 5, 6, 7, 8, 9}, {i, 2, 50}], 1], PrimeQ[ # ] &]

CROSSREFS

Cf. A090148, A090149, A090150, A090151, A090152, A090153, A090154, A090155, A090157.

Sequence in context: A133535 A045715 A113891 * A162674 A070845 A093297

Adjacent sequences:  A090154 A090155 A090156 * A090158 A090159 A090160

KEYWORD

nonn,base

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Nov 22 2003

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 14 18:47 EST 2012. Contains 205663 sequences.