OFFSET
1,1
COMMENTS
Sequence is infinite - see Comments in A078233. - Fung Cheok Yin (cheokyin_restart(AT)yahoo.com.hk), Sep 02 2006
Terms after a(8) have at least 18 digits. - R. J. Mathar, Apr 01 2007
MAPLE
A078237 := proc(nmax) local a, k, anext, baddigs, overl; a := [6] ; baddigs := {1, 2, 3, 5, 7} ; while nops(a) <nmax do k := 2 ; while true do anext := k*op(-1, a) ; overl := baddigs intersect convert(convert(anext, base, 10), set) ; if ( anext mod 10 <> 0) and nops(overl) = 0 then a := [op(a), anext] ; print(a); break ; else k := k+1 ; fi ; od ; od ; RETURN(a) ; end: A078237(20) ; # R. J. Mathar, Apr 01 2007
CROSSREFS
KEYWORD
base,more,nonn
AUTHOR
Amarnath Murthy, Nov 23 2002
EXTENSIONS
a(7) from Jonathan Vos Post, Mar 22 2006
a(8) from R. J. Mathar, Apr 01 2007
More terms from Robert Gerbicz, May 09 2008
a(11) from Donovan Johnson, Sep 05 2008
STATUS
approved