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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A316479 a(n) is the smallest prime whose base-b expansion, read as a base-10 number, is a prime for every b in 2, 3, ..., n. (For n > 10, each base-b expansion for 10 < b <= n must contain no digit larger than 9.) 0
 3, 157, 157, 9241, 9241, 48404791, 18172964503, 50006393431, 50006393431, 181395559296673 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS a(2)=3, the smallest term in A065720, primes whose binary representation is also the decimal representation of a prime; a(3)=157, the smallest integer in both A065720 and A065721, primes p whose base-3 expansion is also the decimal expansion of a prime; similarly, a(4)=157 is the smallest integer in A065720, A065721, and A065722. Is this sequence infinite? a(12) > 10^16. - Giovanni Resta, Aug 01 2018 LINKS Table of n, a(n) for n=2..11. EXAMPLE a(2)=3 because 3 is prime, 3_10 = 11_2, and 11 is prime, and 3 is the smallest such number. a(3)=157 because 157 is prime, 157_10 = 10011101_2, 157_10 = 12211_3, and 10011101 and 12211 are prime, and 157 is the smallest such number. a(4)=157 as well, since 157_10 = 2131_4 and 2131 is also prime. CROSSREFS Cf. A065720, A065721, A065722, A065723, A065724, A065725, A065726, A065727. Cf. A084482, A236537. Sequence in context: A087306 A278877 A203682 * A139964 A048797 A281799 Adjacent sequences: A316476 A316477 A316478 * A316480 A316481 A316482 KEYWORD nonn,base,more AUTHOR Jon E. Schoenfield, Jul 16 2018 EXTENSIONS a(8)-a(10) from Giovanni Resta, Jul 17 2018 a(11) from Giovanni Resta, Jul 24 2018 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.

Last modified April 16 08:27 EDT 2024. Contains 371698 sequences. (Running on oeis4.)