cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A371361 The first of two consecutive primes p, q such that p, q and p + q are all pandigital.

Original entry on oeis.org

10234568791, 10234685971, 10234756849, 10234786589, 10234865779, 10235678449, 10237845649, 10243756981, 10245836789, 10245936781, 10245968371, 10247658389, 10247658923, 10247685893, 10248357659, 10248756893, 10256734879, 10256839447, 10256839477, 10257384679, 10257486913, 10258367429, 10258367489
Offset: 1

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Author

Robert Israel, Mar 19 2024

Keywords

Comments

The first case where a(n) and a(n+1) are consecutive primes is n = 18. Thus p = a(18) = 10256839447, q = a(19) = 10256839477 and r = 10256839487 are three consecutive primes with p, q, r, p + q and q + r all pandigital. In addition, p + r = 20513678934 ia pandigital.

Examples

			a(3) =  10234756849 is a term because it is prime and pandigital, the next prime 10234756859 is also pandigital, and  10234756849 + 10234756859 = 20469513708 is pandigital.
		

Crossrefs

Programs

  • Maple
    ispd:= proc(n) convert(convert(n,base,10),set) = {$0..9} end proc:
    q:=nextprime(10^10): qgood:= false: Res:= NULL: count:= 0:
    while count < 25 do
      p:= q; pgood:= qgood;
      q:= nextprime(p); qgood:= ispd(q);
      if pgood and qgood and ispd(p+q) then
        Res:= Res, p; count:= count+1;
      fi;
    od:
    Res;