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%I #9 Nov 04 2018 20:30:32
%S 1,2,3,4,6,7,8,10,11,12,14,15,18,19,20,22,24,26,27,31,32,34,35,36,38,
%T 39,42,46,47,50,54,55,59,60,62,66,67,70,71,75,78,84,87,90,92,94,98,99,
%U 102,104,106,110,111,115,116,119,122,126,127,130,131,132,138
%N Numbers not of form abcd + abce + abde + acde + bcde for 1 <= a <= b <= c <= d <= e.
%H Robert Israel, <a href="/A027564/b027564.txt">Table of n, a(n) for n = 1..1578</a>
%p N := 1000: # for all terms <= N
%p V:= Vector(N):
%p for a from 1 to floor((N/5)^(1/4)) do
%p for b from a while 4*a*b^3+b^4<= N do
%p for c from b while 3*a*b*c^2 + (a+b)*c^3 <= N do
%p for d from c while 2*a*b*c*d + (b*c+a*c+a*b)*d^2 <= N do
%p for e from d do
%p r:= a*b*c*d+a*b*c*e+a*b*d*e+a*c*d*e+b*c*d*e;
%p if r > N then break fi;
%p V[r]:= 1;
%p od od od od od:
%p select(t -> V[t]=0, [$1..N]); # _Robert Israel_, Nov 04 2018
%Y Cf. A025052, A027563, A027565, A027566.
%K nonn,fini
%O 1,2
%A _R. H. Hardin_
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