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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A069706 Primes with property that swapping first and last digits also gives a prime. 3
2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, 97, 101, 107, 113, 131, 149, 151, 157, 167, 179, 181, 191, 199, 311, 313, 337, 347, 353, 359, 373, 383, 389, 701, 709, 727, 733, 739, 743, 751, 757, 761, 769, 787, 797, 907, 919, 929, 937, 941, 953, 967, 971, 983 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

This is not the same as A007500, "palindromic" primes.

EXAMPLE

1049 and 9041 both are primes hence both are members.

MATHEMATICA

Do[t = IntegerDigits[ Prime[n]]; u = t; u[[1]] = t[[ -1]]; u[[ -1]] = t[[1]]; t = FromDigits[u]; If[ PrimeQ[t], Print[ Prime[n]]], {n, 1, 300}]

CROSSREFS

Cf. A007500, A069707, A069708.

Sequence in context: A086498 A055387 A061461 * A007500 A090933 A107845

Adjacent sequences:  A069703 A069704 A069705 * A069707 A069708 A069709

KEYWORD

nonn,base

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 08 2002

EXTENSIONS

Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Apr 12 2002

Edited by N. J. A. Sloane (njas(AT)research.att.com), Jan 20 2009

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 17 23:08 EST 2012. Contains 206085 sequences.