Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A084201
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A084201 Primes n such that the sum of the digits is prime and the sum of the digits of 2n is also prime. +0
1
7, 29, 47, 61, 83, 137, 139, 151, 173, 191, 193, 227, 229, 263, 281, 283, 317, 337, 353, 373, 409, 461, 463, 557, 577, 599, 601, 641, 643, 733, 757, 797, 821, 823, 887, 911, 977, 1019, 1039, 1051, 1091, 1093, 1109, 1129, 1163, 1181, 1217, 1237, 1291 (list; graph; listen)
OFFSET

0,1

COMMENT

Note that 137 and 139 are twin primes.

A049084(A007953(a(n)))*A049084(A007953(2*a(n))) > 0. - Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), Jun 26 2003

EXAMPLE

2+9=11=prime for 29 and 5+8=13=prime for 58=2*29;

1+3+7=11=prime for 137 and 2+7+4=13=prime for 274=2*137;

1+3+9=13=prime for 139 and 2+7+8=17=prime for 278=2*139.

CROSSREFS

Sequence in context: A075583 A103603 A045465 this_sequence A031380 A005698 A080185

Adjacent sequences: A084198 A084199 A084200 this_sequence A084202 A084203 A084204

KEYWORD

base,nonn

AUTHOR

CAPELLE Patrick (patrick.capelle(AT)clearwire.be), Jun 20 2003

EXTENSIONS

More terms from Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), Jun 26 2003

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified August 19 23:53 EDT 2008. Contains 142930 sequences.


AT&T Labs Research