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A038772 Numbers not divisible by any of their digits. 24
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A038769(a(n)) = 0; complement of A038770.

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

CROSSREFS

Cf. A034709, A034837, A038769, A038770.

Sequence in context: A025059 A160774 A163142 * A188454 A178960 A282713

Adjacent sequences:  A038769 A038770 A038771 * A038773 A038774 A038775

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

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Last modified May 23 08:43 EDT 2017. Contains 286909 sequences.