

A167847


Straightline primes.


3



11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 4567, 76543, 23456789, 1111111111111111111, 11111111111111111111111
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Prime numbers with 2 digits together with the primes whose digits are in arithmetic progression. The structure of digits represents a straight line.
Note that in the graphic representation the points are connected by imaginary line segments (see also A135643).
Note that all twodigit primes are straightline primes but this sequence has no threedigit terms.
No further terms between 23456789 and 115507867=prime(6600000).  R. J. Mathar, Dec 04 2009
All terms after 23456789 are repunit primes (A004022) with number of digits: 19, 23, 317, 1031, 49081, 86453, 109297, 270343, ... (A004023).  Jens Kruse Andersen, Jul 21 2014


LINKS

Table of n, a(n) for n=1..26.


EXAMPLE

The number 4567 is straightline prime:
. . . .
. . . .
. . . 7
. . 6 .
. 5 . .
4 . . .
. . . .
. . . .
. . . .
. . . .


CROSSREFS

Cf. A000040, A004022, A004023, A134811, A134951, A134971, A135643, A167841, A167842, A167843, A167844, A167845, A167846, A167853.
Sequence in context: A108871 A347819 A268031 * A135779 A135778 A078875
Adjacent sequences: A167844 A167845 A167846 * A167848 A167849 A167850


KEYWORD

base,nonn


AUTHOR

Omar E. Pol, Nov 14 2009


EXTENSIONS

2 more terms from R. J. Mathar, Dec 04 2009
a(25)a(26) from Jens Kruse Andersen, Jul 21 2014


STATUS

approved



