A239211 Squares that are not divisible by any of their nonzero digits.

49, 289, 529, 676, 2209, 2809, 4489, 5329, 5776, 5929, 6889, 7396, 8836, 9409, 20449, 24649, 26569, 27889, 29929, 30976, 34969, 37249, 37636, 38809, 49729, 54289, 55696, 59536, 64009, 65536, 66049, 67600, 75076, 76729, 80089, 82369, 85849, 94249, 97969

Offset: 1

Author

Colin Barker, Mar 12 2014

Keywords

• nonn
• base

Comments

Intersection of A000290 and A038772.

The sequence is infinite since it contains all the terms (5*10^k+3)^2, k>0. - Giovanni Resta, Mar 12 2014

Examples

			2809 is in the sequence because 2809 is not divisible by 2, 8 or 9.
		

Links

• Colin Barker, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A239210, A239212, A239213.

Cf. A000290, A038772.

Programs

Mathematica

Select[Range[350]^2,NoneTrue[#/(IntegerDigits[#]/.(0->Nothing)), IntegerQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 08 2017 *)

PARI

isOK(n) = my(v=vecsort(digits(n^2), , 8)); for(i=1+(v[1]==0), #v, if(n^2%v[i]==0, return(0))); 1
s=[]; for(n=1, 1000, if(isOK(n), s=concat(s, n^2))); s