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A104211
Integers n such that the sum of the digits of n is not prime.
8
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
1,2
LINKS
EXAMPLE
Sum of digits of 15=6 not prime.
MATHEMATICA
Select[Range[250], !PrimeQ[Total[IntegerDigits[ # ]]]&] (* Vincenzo Librandi, Apr 17 2013 *)
PROG
(PARI) lista(n) = { my(x, y); for(x=1, n, y=sumdigits(x); if(!isprime(y), print1(x, ", ") ) ); }
CROSSREFS
Complement of A028834.
Sequence in context: A116661 A109104 A073303 * A132858 A071941 A188654
KEYWORD
easy,nonn,base
AUTHOR
Cino Hilliard, Mar 13 2005
STATUS
approved