login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A130122 Primes prime(n) such that 10*prime(n)+prime(n+2) is prime. 1
3, 5, 7, 11, 13, 17, 41, 67, 89, 101, 109, 181, 193, 199, 223, 227, 283, 313, 337, 347, 367, 419, 421, 449, 461, 479, 491, 587, 641, 647, 709, 727, 773, 811, 823, 827, 857, 859, 863, 881, 887, 911, 953, 1021, 1049, 1063, 1091, 1181, 1217, 1361, 1399, 1447 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

a(7)=41 because 10*41+47=457 and 457 is prime,

a(8)=67 because 10*67+73=743 and 743 is prime,

a(9)=89 because 10*89+101=991 and 991 is prime, ...

MAPLE

ts_p6_01:=proc(n) local a, b, i, ans; ans := [ ]: for i from 1 to n do a := 10*ithprime(i)+ithprime(i+2): if (isprime(a)=true) then ans := [ op(ans), ithprime(i) ]: fi od; RETURN(ans) end: ts_p6_01(1000);

MATHEMATICA

Select[Partition[Prime[Range[300]], 3, 1], PrimeQ[10#[[1]]+#[[3]]]&][[All, 1]] (* Harvey P. Dale, Apr 17 2017 *)

CROSSREFS

Cf. A129900.

Sequence in context: A136187 A333207 A328489 * A288893 A046494 A287441

Adjacent sequences: A130119 A130120 A130121 * A130123 A130124 A130125

KEYWORD

nonn

AUTHOR

Jani Melik, Aug 01 2007

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 29 13:28 EST 2022. Contains 358430 sequences. (Running on oeis4.)