OFFSET
1,1
COMMENTS
Differs from A139819 (the latter contains 100, for example). - R. J. Mathar, Jan 17 2017
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, Digit
MAPLE
isA280824 := proc(n)
if n < 10 then
return false;
end if;
dgs := convert(n, base, 10) ;
if type(nops(dgs), 'even') then
type(nops(convert(dgs, set)), 'even') ;
else
false;
end if;
end proc: # R. J. Mathar, Jan 17 2017
MATHEMATICA
Select[Range[1010], Mod[Length[IntegerDigits[#1]], 2] == 0 && Mod[Length[Union[IntegerDigits[#1]]], 2] == 0 & ]
PROG
(Python)
def ok(n): s = str(n); return len(s)%2 == 0 == len(set(s))%2
print(list(filter(ok, range(1011)))) # Michael S. Branicky, Oct 12 2021
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Ilya Gutkovskiy, Jan 08 2017
STATUS
approved