OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
EXAMPLE
87 is a term: 87 and 8+7=15 are composite.
PROG
(PARI) lista(N) = my(s); for(n=2, N, s=sumdigits(n); if(!isprime(n)&&!isprime(s)&&s>1, print1(n, ", ") ) ) \\ Joerg Arndt, Aug 04 2013
(PARI) list(N)=my(v=List(), s); forcomposite(n=4, N, s=sumdigits(n); if(s>1 && !isprime(s), listput(v, n))); Vec(v) \\ Charles R Greathouse IV, Aug 13 2013
(Magma) [n: n in [4..200] | not IsPrime(n) and not IsPrime(&+Intseq(n))]; // Bruno Berselli, Aug 13 2013
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Derek Orr, Aug 02 2013
STATUS
approved