A107743 - OEIS

%I #8 Oct 12 2016 15:59:28

%S 2,3,4,5,6,7,8,9,12,15,17,18,20,21,22,23,24,25,26,27,28,29,30,31,33,

%T 36,38,39,40,41,42,43,44,45,46,47,48,49,50,51,54,55,57,60,61,62,63,64,

%U 65,66,67,68,69,70,72,74,75,77,78,79,80,81,82,83,84,85,86,87,88,89,90,93

%N Numbers m such that m+(digit sum of m) is a composite number.

%C Complement of A047791.

%H Reinhard Zumkeller, <a href="/A107743/b107743.txt">Table of n, a(n) for n = 1..10000</a>

%e A062028(21)=21+(2+1)=24=2*2*2*3, therefore 21 is a term.

%t Select[Range[100],CompositeQ[#+Total[IntegerDigits[#]]]&] (* _Harvey P. Dale_, Oct 12 2016 *)

%o (Haskell)

%o a107743 n = a107743_list !! (n-1)

%o a107743_list = filter ((== 0) . a010051' . a062028) [1..]

%o -- _Reinhard Zumkeller_, Sep 27 2014

%Y Cf. A007953, A062028.

%Y Cf. A010051.

%K nonn,base

%O 1,1

%A _Reinhard Zumkeller_, May 23 2005