A062182 Harmonic mean of digits is 4.

4, 36, 44, 63, 288, 346, 364, 436, 444, 463, 634, 643, 828, 882, 2488, 2666, 2848, 2884, 3366, 3446, 3464, 3636, 3644, 3663, 4288, 4346, 4364, 4436, 4444, 4463, 4634, 4643, 4828, 4882, 6266, 6336, 6344, 6363, 6434, 6443, 6626, 6633, 6662, 8248, 8284

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

Cf. A062179-A062185, A061383-A061388, A061423-A061425.

Sequence in context: A198642 A327998 A274891 * A308531 A073771 A219247

Adjacent sequences: A062179 A062180 A062181 * A062183 A062184 A062185

Keyword

base,easy,nonn

Author

Vladeta Jovovic, Jun 12 2001

Extensions

More terms from Henry Bottomley, Jul 25 2001

Status

approved