OFFSET
1,1
COMMENTS
Numbers ending in zero are not listed because of the form a(n) * 10^k, with k>0.
LINKS
Paolo P. Lava, First 250 terms with their ratios
EXAMPLE
36 = concat(3,6) and 36 / (3*6) = 2;
3375 = concat(3,375) and 3375 / (3*375) = 3;
18144 = concat(18,144) and 18144 / (18*144) = 7.
MAPLE
P:=proc(q) local a, k, n; for n from 1 to q do if not n mod 10=0 then
for k from 1 to ilog10(n) do a:=n/((n mod 10^k)*trunc(n/10^k));
if type(a, integer) then print(n); break; fi; od; fi; od; end: P(10^9);
MATHEMATICA
cxyQ[n_]:=Module[{idn=IntegerDigits[n]}, idn[[-1]]!=0&&AnyTrue[ Table[ FromDigits/@TakeDrop[idn, k], {k, Length[idn]-1}], Divisible[n, Times@@#]&]]; Select[Range[20000], cxyQ] (* The program uses the AnyTrue function from Mathematica version 10 *)(* Harvey P. Dale, Mar 09 2018 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Paolo P. Lava, May 25 2017
STATUS
approved