The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A229908 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A229908

The least prime that has at least n embedded primes, reading forward and backward.
(history; published version)

#14 by Giovanni Resta at Sat Jan 25 10:33:16 EST 2014

STATUS

editing

proposed

#13 by Giovanni Resta at Sat Jan 25 10:32:51 EST 2014

LINKS

Giovanni Resta, <a href="/A229908/b229908.txt">Table of n, a(n) for n = 1..65</a> (terms < 3.5*10^12)

Giovanni Resta, <a href="/A229908/b229908.txt">Table of n, a(n) for n = 1..65</a>

#12 by Giovanni Resta at Sat Jan 25 10:31:55 EST 2014

LINKS

C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_724.htm"> Puzzle 724. Extending the OEIS sequence A229908</a>

Giovanni Resta, <a href="/A229908/b229908.txt">Table of n, a(n) for n = 1..65</a>

#11 by Giovanni Resta at Sat Jan 25 10:28:56 EST 2014

DATA

2, 13, 13, 37, 113, 113, 137, 1237, 1373, 1733, 1733, 11317, 11731, 12713, 19973, 91733, 113173, 113371, 113371, 173347, 991733, 1123379, 1134673, 1137991, 1237199, 2333719, 7433719, 11133719, 11399173, 11399173, 11791733, 37914713, 97433719, 113217397, 113217397, 113337199, 113337199, 113337199, 1113371999, 1113371999, 1113991733, 1139917321, 1139917321, 1139917333

EXTENSIONS

Missing a(19) from Giovanni Resta, Jan 25 2014

STATUS

approved

editing

#10 by Ralf Stephan at Sun Dec 22 10:22:29 EST 2013

STATUS

proposed

approved

#9 by Charles R Greathouse IV at Thu Dec 19 19:55:41 EST 2013

STATUS

editing

proposed

Discussion

Fri Dec 20

09:04

Carlos Rivera: Tomorrow I'm leaving for Christmas holidays. I will attend your recommendation ("Perhaps you should submit the sequence "number of embedded primes in n, reading forward and backward" as well, and cross-reference it here."). For the moment I agreee with all the changes from the review. Thanks!

#8 by Charles R Greathouse IV at Thu Dec 19 19:55:12 EST 2013

CROSSREFS

Cf. A039993, A039997.

Discussion

Thu Dec 19

19:55

Charles R Greathouse IV: Perhaps you should submit the sequence "number of embedded primes in n, reading forward and backward" as well, and cross-reference it here.

#7 by Charles R Greathouse IV at Thu Dec 19 19:54:03 EST 2013

NAME

The least prime P that has embedded at least n embedded primes, reading P forward and backward.

EXAMPLE

Example: for n=a(8, P) = 1237, because there are embedded the following eight embedded primes: 1237, 2, 23, 3, 37, 7 and 73, 7321.

CROSSREFS

Cf. A039997.

KEYWORD

nonn,more,hard,base,changed

STATUS

proposed

editing

#6 by Carlos Rivera at Thu Dec 19 18:03:25 EST 2013

STATUS

editing

proposed

#5 by Carlos Rivera at Thu Dec 19 18:03:11 EST 2013

NAME

allocated for Carlos RiveraThe least prime P that has embedded at least n primes, reading P forward and backward.

DATA

2, 13, 13, 37, 113, 113, 137, 1237, 1373, 1733, 1733, 11317, 11731, 12713, 19973, 91733, 113173, 113371, 173347, 991733, 1123379, 1134673, 1137991, 1237199, 2333719, 7433719, 11133719, 11399173, 11399173, 11791733, 37914713, 97433719, 113217397, 113217397, 113337199, 113337199, 113337199, 1113371999, 1113371999, 1113991733, 1139917321, 1139917321, 1139917333

OFFSET

1,1

COMMENTS

Results of my search up to 2^32.

EXAMPLE

Example: for n=8, P= 1237, because there are embedded the following eight primes: 1237, 2, 23, 3, 37, 7 and 73, 7321

KEYWORD

allocated

nonn,more,hard

AUTHOR

Carlos Rivera, Dec 19 2013

STATUS

approved

editing