OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
filter:= proc(n) local L;
L:= convert(n, base, 10);
if has(L, 0) then return false fi;
nops(L)/add(1/i, i=L)=4
end proc:
select(filter, [$1..10^4]); # Robert Israel, Aug 20 2018
MATHEMATICA
Do[ h = IntegerDigits[n]; If[ Sort[h][[1]] != 0 && Length[h]/Apply[Plus, 1/h] == 4, Print[n]], {n, 1, 10^5}]
hm4Q[n_]:=DigitCount[n, 10, 0]==0&&HarmonicMean[IntegerDigits[n]]==4; Select[Range[9000], hm4Q] (* Harvey P. Dale, Mar 23 2011 *)
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Vladeta Jovovic, Jun 12 2001
EXTENSIONS
More terms from Henry Bottomley, Jul 25 2001
STATUS
approved