A155088 Numbers n such that n and prime(n) contain prime digits only.

2, 3, 55, 332, 352, 375, 733, 3573, 3575, 7235, 22222, 22223, 22322, 252323, 252335, 253777, 255225, 372755, 372772, 522532, 523255, 525737, 2275325, 2275327, 2275337, 2277333, 2277337, 3325772, 27727257, 27727277, 27727732, 27737332, 27737722, 27737723

Offset

1,1

Comments

Indices n such that A045532(n) is in A046034. [R. J. Mathar, May 05 2010]

Links

Giovanni Resta, Table of n, a(n) for n = 1..200

Giovanni Resta, Table of a(n), prime(a(n)) for n = 1..200

Example

352 is in the sequence since 352 and prime(352) = 2377 use only prime digits (2, 3, 5, 7). For more examples see Links.

Mathematica

pQ[n_] := Union[IntegerDigits@n, {2, 3, 5, 7}] == {2, 3, 5, 7}; Select[Range[10^5], pQ@# && pQ@Prime@# &] (* Giovanni Resta, Mar 11 2013 *)
Select[Flatten[Table[FromDigits/@Tuples[{2, 3, 5, 7}, n], {n, 8}]], AllTrue[ IntegerDigits[Prime[#]], PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jun 24 2015 *)

Crossrefs

Cf. A000027, A000040, A167483.

Sequence in context: A339920 A344732 A037424 * A072871 A041709 A361095

Adjacent sequences: A155085 A155086 A155087 * A155089 A155090 A155091

Keyword

nonn,base

Author

Juri-Stepan Gerasimov, Jan 20 2009

Extensions

Corrected (332, 352, 375 inserted) by R. J. Mathar, May 05 2010

a(11)-a(34) from Giovanni Resta, Mar 11 2013

Status

approved