A274218 Numbers such that the sum of their digits is equal to the sum of digits of their aliquot parts.

6, 33, 87, 249, 303, 519, 573, 681, 843, 951, 1059, 1329, 1383, 1923, 1977, 2463, 2733, 2787, 2949, 3057, 3273, 3327, 3543, 3651, 3867, 3921, 4083, 4353, 4677, 5163, 5433, 5703, 5919, 6081, 6243, 6297, 6621, 6891, 7053, 7323, 7377, 7647, 7971, 8079, 8133, 8187

Offset

1,1

Links

Paolo P. Lava, Table of n, a(n) for n = 1..1000

Example

Sum of digits of 8884 is 8 + 8 + 8 + 4 = 28. Its aliquot parts are 1, 2, 4, 2221, 4442 and their sum is 1 + 2 + 4 + 2 + 2 + 2 + 1 + 4 + 4 + 4 + 2 = 28.

Maple

with(numtheory): T:=proc(w) local x, y, z; x:=w; y:=0; for z from 1 to ilog10(x)+1 do
y:=y+(x mod 10); x:=trunc(x/10); od; y; end:
P:=proc(q) local a, k, n; for n from 1 to q do a:=sort([op(divisors(n))]);
if T(n)=add(T(a[k]), k=1..nops(a)-1) then print(n); fi; od; end: P(10^6);

Mathematica

Select[Range[10^4], Total@ IntegerDigits@ # == Total[Total@ IntegerDigits@ # & /@ Most@ Divisors@ #] &] (* Michael De Vlieger, Jun 14 2016 *)

Crossrefs

Cf. A007953, A006753.

Sequence in context: A073343 A157872 A153127 * A135526 A204185 A057818

Adjacent sequences: A274215 A274216 A274217 * A274219 A274220 A274221

Keyword

nonn,base,easy

Author

Paolo P. Lava, Jun 14 2016

Status

approved