A091783 Numbers with digits in nondecreasing order such that sum of the reciprocals of the digits is 1.

1, 22, 236, 244, 333, 2488, 2666, 3366, 3446, 4444, 26999, 28888, 33999, 34688, 36666, 44488, 44666, 55555, 366999, 368888, 446999, 448888, 466688, 666666, 3999999, 4688999, 4888888, 6666999, 6668888, 7777777, 66999999, 68888999, 88888888, 999999999

Offset

1,2

Comments

236 is a member but 263, 326, 362, 623, 632 which are digit permutations of 236 are not included (unlike A037268).

By definition, this is a subsequence of A052382 (zeroless numbers). - Michel Marcus, Jul 06 2015

Links

Table of n, a(n) for n=1..34.

Example

236 is a member as 1/2 + 1/3 + 1/6 = 1.

Maple

F:= proc(t, ns) option remember;
   local n0, k, r;
   if ns = [] then
      if t = 0 then return {[]}
      else return {}
      fi;
   fi;
   n0:= ns[1];
   `union`(seq(map(r -> [k, op(r)], procname(t - k/n0, ns[2..-1])), k=0..floor(t*n0)));
end proc:
g:= proc(t) local L, i; L:= [seq(i$t[i], i=1..9)]; add(L[i]*10^(nops(L)-i), i=1..nops(L)) end proc:
sort(convert(map(g, F(1, [$1..9])), list)); # Robert Israel, Jul 06 2015

Prog

(PARI) lista(nn) = {for (n=1, nn, d = digits(n); if (vecmin(d) && (vecsort(d)==d) && (sum(k=1, #d, 1/d[k])==1), print1(n, ", ")); ); } \\ Michel Marcus, Jul 06 2015

Crossrefs

Cf. A037268, A052382.

Sequence in context: A082205 A003205 A037268 * A213072 A159649 A046499

Adjacent sequences: A091780 A091781 A091782 * A091784 A091785 A091786

Keyword

base,fini,nonn,full

Author

Amarnath Murthy, Feb 17 2004

Extensions

More terms from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Apr 17 2004

Incorrect term 39999 corrected to 33999 by Thomas Oléron Evans, Jul 06 2015

Status

approved