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

1,1

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

Links

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

Example

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

Mathematica

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

Prog

(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

Crossrefs

Cf. A239210, A239212, A239213.

Cf. A000290, A038772.

Sequence in context: A158248 A219030 A167719 * A198437 A144407 A089552

Adjacent sequences: A239208 A239209 A239210 * A239212 A239213 A239214

Keyword

nonn,base

Author

Colin Barker, Mar 12 2014

Status

approved