The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A248620 Lesser of twin primes of (29n + 1, 29n + 3). 2
59, 1277, 1451, 3539, 4931, 5279, 9281, 9629, 10499, 11717, 12239, 16067, 22157, 23027, 23201, 24419, 26681, 31727, 34511, 35729, 37991, 40427, 45821, 47387, 48779, 55217, 59219, 60089, 70181, 70877, 72269, 75401, 77489, 79229, 80447, 83231, 85667, 88799 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Lesser of twin primes where A195819(n) + 1 and A195819(n) + 3 are both primes.
Intersection of A001359 and A141977.
LINKS
EXAMPLE
29 * 2 + 1 = 59, which is prime, and 61 is also prime, so 59 is in the sequence.
29 * 44 + 1 = 1277, which is prime, and 1279 is also prime, so 1277 is in the sequence.
29 * 50 + 1 = 1451, which is prime, and 1453 is also prime, so 1451 is in the sequence.
29 * 54 + 1 = 1567, which is prime, but 1569 = 3 * 523, so 1567 is not in the sequence.
MATHEMATICA
Select[58Range[1500] + 1, PrimeQ[#] && PrimeQ[# + 2] &] (* Alonso del Arte, Oct 31 2014 *)
Select[29*Range[2, 3150, 2], AllTrue[#+{1, 3}, PrimeQ]&]+1 (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Mar 16 2019 *)
PROG
(Python)
from math import *
from sympy import isprime
for n in range(0, 10001):
..if isprime(58*n+1) and isprime(58*n+3): print (58*n+1, end=', ')
(PARI) lista(nn) = {forstep (n=2, nn, 2, if (isprime(p=29*n+1) && isprime(29*n+3), print1(p, ", ")); ); } \\ Michel Marcus, Oct 17 2014
CROSSREFS
Cf. A001359 (Lesser of twin primes), A195819 (Multiples of 29).
Cf. A141977 (Primes congruent to 1 mod 29), A141979 (Primes congruent to 3 mod 29).
Sequence in context: A336576 A248974 A245941 * A210398 A278366 A134652
KEYWORD
nonn
AUTHOR
Karl V. Keller, Jr., Oct 10 2014
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 June 6 06:26 EDT 2024. Contains 373115 sequences. (Running on oeis4.)