OFFSET
1,2
FORMULA
a(n) = 2^(n-4) if n > = 5.
EXAMPLE
MAPLE
nn:=2000:Digits:=nn:T:=array(1..nn):for n from 1 to nn do: T[n]:= irem(floor((1.5 ^n)*10^n), 10^n): od: for a from 1 to nn do: z1:=T[a]: ii:=0:k:=0:for b from a+1 to nn while(ii)=0 do:k:=k+1: z2:=irem(T[b], 10^a): if z1=z2 then ii:=1:printf(`%d, `, k): else fi:od:od:
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Dec 30 2009, Apr 22 2010
EXTENSIONS
More terms and edits. - Michel Lagneau, Jul 14 2012
STATUS
approved