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
Exponential density 0.954... = A104139. Asymptotically 8/35 * n^0.954... + O(n^0.903...) members up to n. - Charles R Greathouse IV, Jul 22 2012
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
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 !! (n-1)
a038772_list = filter p [1..] where
p n = all (> 0) $ map ((mod n) . digitToInt) $ filter (> '0') $ show n
-- Reinhard Zumkeller, Jun 19 2011
(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')
print(list(filter(ok, range(1, 339)))) # Michael S. Branicky, May 20 2021
CROSSREFS
KEYWORD
base,easy,nonn,nice
AUTHOR
Henry Bottomley, May 04 2000
EXTENSIONS
Edited by N. J. A. Sloane, Nov 17 2008 at the suggestion of R. J. Mathar
STATUS
approved