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Primes whose base c expansion is also the base b expansion of a prime.
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Primes whose base c expansion is also the base b expansion of a prime.

by M. F. Hasler, Jan.2014 - under construction : seq’s in yellow = submitted as draft, green = published

b \c  

2

3

4

5

6

7

8

9

10

other

(b,c)

2

(A000040)

73, 521, 577,...
=
A235265

2,5,7,11,31,37...
=
A235461

⊂ A077718

5,31,131,151,...
=
A235462
⊂ A077719

...
=
A235263
⊂ A077720

...
=
A235464
⊂ A077721

...
=
A235465
⊂ A077722

739,811,6571,...
=
A235466
⊂ A077723

11,101,10111,...
=
A089971
A020449

(10,13):
A090712

(13,10):
A235110

3

2,7,11,13,41,...
=
A235266

(A000040)

2,89,137,149,...
=
A235467

...
=
A235468

2,13,43,73,...
=
A235469 

2,7,107,401,...
=
A235470 

2,17,73,521,...
=
A235471 

2,11,19,83,...
=
A235472

A089981

(10,17):
A090713

(17,10):
A235126

4

A152079

2,43,61,67,97...
=
A235473

(A000040)

...13,41,43,61...
=
A235615

...7,19,37,79...
=
A235616

...17,59,71,73...
=
A235617

...11,19,67,89...
=
A235618

...
=
A235619

A090707

(10,19):
A090714

(19,10):
A235144

5

2,7,11,13,19,...
=
A235475 

...
=
A231474

2,3,11,29,31,...
=
A235474 

(A000040)

...
=
A235626

...7,17,23,31...
=
A235627

...17,19,73,89...
=
A235628

...11,19,29,31...
=
A235629

A090708

(10,31):
A090715

A235640 ?

6

3,5,7,11,17,19...
=
A235476 

...
=  
A231476

2,3,5,13,17,...
=
A235624

2,3,11,31,71,...
=
A235625 

(A000040)

...5,19,61,89...
=
A235637

...13,17,29,37...
=
A235638

...5,19,23,41...
=
A235639

A090709

(10,32):
A090716

A235641 ?

7

2, 31, 47, 59,...
=
A235477

...
=
A231477 

2,3,11,23,29...
=
A235634

...,5,13,17,23...
=
A235635

2,3,5,17,47,...
=
A235636

(A000040)

...5,19,53,89...
=
A235622

...19,41,59,97...
=
A235621

A090710

 (10,64):
A090717...

A235642 ?

8

...
=
A235478

2,7,13,31,37...
=
A231478

2,3,7,11,19,29...
=
A235633

2,3,11,13,31...
=
A235632

2,3,5,11,13,23...
=
A235631

2,3,5,17,47,...
=
A235630

(A000040)

...19,41,59,97...
=
A235620

A235394

(by RGWv)

...(10,512):
A090720

A235643 ?

9

11,13,19,41,...
=
A235479

2,5,7,11,17,19...
=
A235480

2,3,29,41,61,...
=
A235481

2,3,7,11,17,19...
=
A235482 

...13,17,29;59...
=
A231481

2,5,7,11,17,19...
=
A231479

...17,37,53,79...
=
A231480

(A000040)

A235395
(by RGWv)

(10,1024):
A090721

A235644 ?

10

A065720
A036952

A065721

A065722

A065723

A065724

A065725

A065726

A065727

(A000040)

(10,11):
A090711

(11,10):
A091924

*since primes < min(b,c) are always in the sequence, some initial terms are omitted above, at the profit of one more larger term.

Useful PARI code:
is(p,b=2,c=3)=vecmax(d=digits(p,c))<b&&isprime(vector(#d,i,b^(#d-i))*d~)&&isprime(p)
r(p,b,c)=sum(i=1,#p=digits(p,c),p[i]*b^(#p-i)) \\ “rebase” from base c to base b

forprime(p=1,999,is(p,b,c)&&print1(p","))

forprime(p=1,999,is(p,b,c)&&print1(r(p,b,c)",")) \\ for c < b