A104211 Integers n such that the sum of the digits of n is not prime.

1, 4, 6, 8, 9, 10, 13, 15, 17, 18, 19, 22, 24, 26, 27, 28, 31, 33, 35, 36, 37, 39, 40, 42, 44, 45, 46, 48, 51, 53, 54, 55, 57, 59, 60, 62, 63, 64, 66, 68, 69, 71, 72, 73, 75, 77, 78, 79, 80, 81, 82, 84, 86, 87, 88, 90, 91, 93, 95, 96, 97, 99, 100, 103, 105, 107, 108, 109, 112

Offset: 1

Author

Cino Hilliard, Mar 13 2005

Keywords

• easy
• nonn
• base

Examples

			Sum of digits of 15=6 not prime.
		

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Crossrefs

Complement of A028834.

Cf. A000040, A007953.

Programs

Mathematica

Select[Range[250], !PrimeQ[Total[IntegerDigits[ # ]]]&] (* Vincenzo Librandi, Apr 17 2013 *)

PARI

lista(n) = { my(x,y); for(x=1,n, y=sumdigits(x); if(!isprime(y), print1(x,", ") ) ); }