A153025 Numbers n with property that n and n^2 use only prime digits.

5, 235, 72335

Offset

1,1

Comments

Probably there are no other terms. No other terms up to 10^40.

Intersection of A046034 and A275971. - M. F. Hasler, Sep 16 2016

Links

Table of n, a(n) for n=1..3.

Example

The squares of 5, 235, 72335 are 25, 55225, 5232352225.

Mathematica

Flatten[Table[Select[FromDigits/@Tuples[{2, 3, 5, 7}, n], AllTrue[ IntegerDigits[ #^2], PrimeQ]&], {n, 5}]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Oct 16 2014 *)

Crossrefs

Cf. A046034, A275971.

Sequence in context: A157710 A265957 A137085 * A140518 A269551 A200962

Adjacent sequences: A153022 A153023 A153024 * A153026 A153027 A153028

Keyword

nonn,bref,base

Author

Zak Seidov, Dec 17 2008

Extensions

Edited by David Wilson and N. J. A. Sloane, Jan 25 2009

Status

approved