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Numbers that cannot be expressed as the sum of distinct odd composite numbers.
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%I #6 May 02 2015 15:56:35

%S 1,2,3,4,5,6,7,8,10,11,12,13,14,16,17,18,19,20,22,23,26,28,29,31,32,

%T 37,38,41,43,47,53

%N Numbers that cannot be expressed as the sum of distinct odd composite numbers.

%t lim = 120; Complement[Range@ 120, TakeWhile[Plus @@@ Subsets[Select[Range@ lim, OddQ@ # && CompositeQ@ # &], 5], # < 5 lim &]] (* _Michael De Vlieger_, Apr 27 2015 *)

%o (PARI) alist(n) = local(poly=1+x*x^n);forstep(k=9,n,2,if(!isprime(k),poly*=1+x^k));for(k=1,n,if(polcoeff(poly,k)==0,print1(k", ")))

%Y Cf. A071904.

%K nonn,fini,full

%O 1,2

%A _Franklin T. Adams-Watters_, Apr 27 2015