A263404 Smallest square containing the first n primes as substrings.

25, 324, 3025, 35721, 11730625, 71132356, 1132591716, 17136119025, 1923311317225, 58191311792329, 58191311792329, 231372178511929, 1722376411319529, 1134152319174379129, 472643754131992311729, 17298113195343723473641, 419723711317595314724329, 4319231361106417537475929

Offset: 1

Author

Emmanuel Vantieghem, Oct 17 2015

Keywords

• nonn
• base

Comments

The sequence is infinite.

Examples

			a(6) = 71132356 = 8464^2 contains 2, 3, 5, 7, 11 and 13 as substrings and no smaller square has that property.
		

Crossrefs

Cf. A054261, A069600.

Programs

Mathematica

Do[k = 1; While[! AllTrue[Prime@ Range@ n, StringContainsQ[ToString[k^2], ToString@ #] &], k++]; Print[k^2], {n, 9}] (* Michael De Vlieger, Oct 19 2015, Version 10 *)

Extensions

a(15)-a(16) from Bert Dobbelaere, Oct 28 2018

a(17)-a(18) from Giovanni Resta, Aug 27 2019