OFFSET
1,1
COMMENTS
This is a regular language in base 10. Almost all members of this sequence are multiples of either 42 or 105. There are about 2/63 * 3^n members of this sequence up to 10^n. - Charles R Greathouse IV, Nov 09 2011
LINKS
Harry J. Smith and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 1000 terms from Smith)
EXAMPLE
77322 is divisible by 7, 3 and 2.
MATHEMATICA
Select[Range[2, 50000], Complement[IntegerDigits[#], FactorInteger[#][[All, 1]]] == {} &] (* Alonso del Arte, Dec 05 2011 *)
PROG
(PARI) { n=0; for (m=1, 10^10, t=m; b=1; while (t>0, d=t%10; t=(t-d)/10; if (!isprime(d) || m%d, b=0; break)); if (b, write("b062239.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Feb 17 2010
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Erich Friedman, Jun 30 2001
STATUS
approved