A160947 - OEIS

%I #20 Mar 08 2024 01:13:06

%S 9,10,12,16,40,42,55,90,96,99,100,105,120,130,154,156,160,180,187,220,

%T 231,232,238,253,270,273,300,304,310,352,360,364,384,390,400,420,450,

%U 451,490,493,507,520,528,540,550,598,609,616,624,630,646,649,672,684

%N Numbers k that are multiples of the digital sum of k+1.

%H Muniru A Asiru, <a href="/A160947/b160947.txt">Table of n, a(n) for n = 1..1900</a>

%e 232 is in the sequence because 232 = 29 * ds(233) = 29*8.

%e 684 is in the sequence because 684 = 36 * ds(685) = 36*19.

%t Select[Range[800], Divisible[#, Total[IntegerDigits[# + 1]]] &] (* _Vincenzo Librandi_, Apr 18 2018 *)

%o (PARI) isok(n) = !(n % sumdigits(n+1)); \\ _Michel Marcus_, Apr 17 2018

%o (GAP) a:=List(Filtered(List([1..700],m->[m,List(List(List([1..m],n->n+1),ListOfDigits),Sum)[m]]),i->i[1] mod i[2]=0),j->j[1]); # _Muniru A Asiru_, Apr 17 2018

%o (Magma) [n: n in [1..800] | n mod &+Intseq(n+1) eq 0]; // _Vincenzo Librandi_, Apr 18 2018

%Y Cf. A007953, A160948.

%K nonn,base

%O 1,1

%A _Claudio Meller_, May 30 2009