

A038772


Numbers not divisible by any of their digits.


31



23, 27, 29, 34, 37, 38, 43, 46, 47, 49, 53, 54, 56, 57, 58, 59, 67, 68, 69, 73, 74, 76, 78, 79, 83, 86, 87, 89, 94, 97, 98, 203, 207, 209, 223, 227, 229, 233, 239, 247, 249, 253, 257, 259, 263, 267, 269, 277, 283, 289, 293, 299, 307, 308, 323, 329, 334, 337, 338
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OFFSET

1,1


COMMENTS

This is a regular language when written in decimal, though the minimal regular expression is probably thousands of characters long.  Charles R Greathouse IV, Aug 19 2011


LINKS



EXAMPLE

34 is divisible by neither 3 nor 4.
35 is excluded because 5 is a divisor of 35, but 37 is included because neither 3 nor 7 is a divisor of 37


MATHEMATICA

nddQ[n_]:=Module[{idn=DeleteCases[IntegerDigits[n], 0]}, And@@Table[ !Divisible[n, idn[[i]]], {i, Length[idn]}]]; Select[Range[350], nddQ] (* Harvey P. Dale, Nov 01 2011 *)


PROG

(Haskell)
import Data.Char (digitToInt)
a038772 n = a038772_list !! (n1)
a038772_list = filter p [1..] where
p n = all (> 0) $ map ((mod n) . digitToInt) $ filter (> '0') $ show n
(PARI) is(n)=my(v=vecsort(eval(Vec(Str(n))), , 8)); for(i=if(v[1], 1, 2), #v, if(n%v[i]==0, return(0))); 1 \\ Charles R Greathouse IV, Jul 22 2011
(Magma) [k:k in [1..340] forall{c:c in Set(Intseq(k)) diff {0}k mod c ne 0}]; // Marius A. Burtea, Dec 22 2019
(Python)
def ok(n): return not any(n%int(d) == 0 for d in str(n) if d != '0')


CROSSREFS



KEYWORD

base,easy,nonn,nice


AUTHOR



EXTENSIONS



STATUS

approved



