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.

A090711 Primes whose base-11 expansion is a (valid) decimal expansion of a prime.

Original entry on oeis.org

2, 3, 5, 7, 31, 47, 67, 73, 97, 163, 223, 227, 229, 271, 311, 317, 331, 397, 421, 443, 449, 557, 683, 727, 733, 773, 883, 953, 977, 991, 997, 1063, 1109, 1129, 1367, 1373, 1433, 1483, 1607, 1613, 1637, 1657, 1697, 1723, 1783, 1871, 1873, 1879, 2027, 2203, 2269
Offset: 1

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Author

Cino Hilliard, Jan 18 2004

Keywords

Comments

See A091924 for the sequence whose definition works "the other way round": Actually, the base-11 representation of the terms of this sequence here. - M. F. Hasler, Jan 03 2014

Examples

			The prime p = 31 is written 29 in base 11, and 29 read in base 10 is again a prime. So 31 is a term.
		

Crossrefs

Cf. A090712.

Programs

  • Mathematica
    b11pQ[n_]:=Module[{d=IntegerDigits[n,11]},Max[d]<10&&PrimeQ[FromDigits[ d]]]; Select[Prime[Range[400]],b11pQ] (* Harvey P. Dale, Apr 17 2018 *)
  • PARI
    is(p,b=10,c=11)=vecmax(d=digits(p,c))M. F. Hasler, Jan 05 2014

Extensions

Edited by N. J. A. Sloane, Feb 07 2007, and by M. F. Hasler, Jan 03 2014