OFFSET
1,1
COMMENTS
MATHEMATICA
f[n_] := Union@Flatten@Table[2^a*3^b*5^c*7^d, {a, 0, Log2[n]}, {b, 0, Log[3, n/2^a]}, {c, 0, Log[5, n/(2^a*3^b)]}, {d, 0, Log[7, n/(2^a*3^b*5^c)]}];
b = Block[{nn = 3000, s}, s = f[nn]; {0, 1}~Join~
Select[Union@Flatten@Outer[Plus, s, s], # <= nn &]];
Complement[Range[3000], b]
CROSSREFS
KEYWORD
nonn
AUTHOR
Carlos Alves, Jan 03 2019
STATUS
approved