OFFSET
1,2
COMMENTS
Numbers of the form 1000...000 and 1000...0001 also belong to A144980.
LINKS
Paolo P. Lava, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = A160947(n-1)+1. [discovered by sequencedb.net]. - R. J. Mathar, Jun 24 2021
EXAMPLE
1-1 = 0 is divisible by 1, hence 1 is in the sequence; 56-1 = 55 is divisible by 5+6 = 11, hence 56 is in the sequence.
MAPLE
with(numtheory): P:=proc(q)local a, b, k, n;
for n from 1 to q do a:=n; b:=0;
for k from 1 to ilog10(n)+1 do b:=b+(a mod 10); a:=trunc(a/10); od;
if type((n-1)/b, integer) then print(n); fi; od; end: P(10^5);
MATHEMATICA
Select[Range[10^3], Mod[#-1, Total[IntegerDigits[#]]]==0&] (* Ivan N. Ianakiev, Mar 25 2015 *)
PROG
(PARI) lista(nn) = for (n=1, nn, if ((n-1) % sumdigits(n) == 0, print1(n, ", "))); \\ Michel Marcus, Mar 25 2015
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Paolo P. Lava, Mar 25 2015
EXTENSIONS
Missing a(5270) in b-file inserted by Andrew Howroyd, Feb 23 2018
STATUS
approved