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.

A092529 Primes p such that both the digit sum of p plus p and the digit product of p plus p are also primes.

Original entry on oeis.org

163, 233, 293, 431, 499, 563, 617, 743, 1423, 1483, 1489, 1867, 2273, 2543, 2633, 3449, 4211, 4217, 4273, 4547, 4729, 5861, 6121, 6529, 6637, 6653, 6761, 6857, 6949, 7681, 8273, 8431, 8837, 8839, 9649, 9689
Offset: 1

Views

Author

Ray G. Opao, Apr 08 2004

Keywords

Comments

Intersection of A048519 and A092518.
Zeros are not permitted in p; thus, for example, 101 is not included. - Harvey P. Dale, May 25 2013

Examples

			a(2) = 233: 233+(2+3+3) = 233+8 = 241, which is prime. 233+(2*3*3) = 233+18 = 251, which is prime.
		

Crossrefs

Programs

  • Maple
    filter:= proc(p) local L;
      if not isprime(p) then return false fi;
      L:= convert(p,base,10);
      if member(0,L) then return false fi;
      isprime(p + convert(L,`+`)) and isprime(p + convert(L,`*`))
    end proc:
    select(filter, [seq(i,i=3..10000,2)]); # Robert Israel, Feb 20 2024
  • Mathematica
    pppQ[n_]:=Module[{idn=IntegerDigits[n]},!MemberQ[idn,0]&&And@@PrimeQ[ {n+ Total[idn], n+Times@@idn}]]; Select[Prime[Range[1200]],pppQ] (* Harvey P. Dale, May 25 2013 *)

Extensions

More terms from Robert G. Wilson v, Apr 10 2004