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Niven (or Harshad) numbers that are not divisible by 3.
1

%I #3 Mar 30 2012 18:50:36

%S 1,2,4,5,7,8,10,20,40,50,70,80,100,110,112,133,140,152,190,200,209,

%T 220,224,230,247,266,280,308,320,322,364,370,392,400,407,410,440,448,

%U 460,476,481,500,506,511,512,518,550,592,605,629,640,644,700,704,715

%N Niven (or Harshad) numbers that are not divisible by 3.

%C a(n) mod A007953(a(n)) = 0 and A007953(a(n)) mod 3 > 0;

%C Intersection of A005349 and A001651.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HarshadNumber.html">Harshad Number</a>

%Y Cf. A085371.

%K nonn,base

%O 1,2

%A _Reinhard Zumkeller_, Jun 26 2003