%I #21 Jun 24 2021 06:16:10
%S 1,10,11,13,17,41,43,56,91,97,100,101,106,121,131,155,157,161,181,188,
%T 221,232,233,239,254,271,274,301,305,311,353,361,365,385,391,401,421,
%U 451,452,491,494,508,521,529,541,551,599,610,617,625,631,647,650,673
%N Natural numbers n such that n-1 is divisible by the sum of the decimal digits of n.
%C Numbers of the form 1000...000 and 1000...0001 also belong to A144980.
%H Paolo P. Lava, <a href="/A253205/b253205.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A160947(n-1)+1. [discovered by sequencedb.net]. - _R. J. Mathar_, Jun 24 2021
%e 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.
%p with(numtheory): P:=proc(q)local a,b,k,n;
%p for n from 1 to q do a:=n; b:=0;
%p for k from 1 to ilog10(n)+1 do b:=b+(a mod 10); a:=trunc(a/10); od;
%p if type((n-1)/b,integer) then print(n); fi; od; end: P(10^5);
%t Select[Range[10^3],Mod[#-1,Total[IntegerDigits[#]]]==0&] (* _Ivan N. Ianakiev_, Mar 25 2015 *)
%o (PARI) lista(nn) = for (n=1, nn, if ((n-1) % sumdigits(n) == 0, print1(n, ", "))); \\ _Michel Marcus_, Mar 25 2015
%Y Cf. A005349, A144967, A144980.
%K nonn,base,easy
%O 1,2
%A _Paolo P. Lava_, Mar 25 2015
%E Missing a(5270) in b-file inserted by _Andrew Howroyd_, Feb 23 2018