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A323051
Numbers that cannot be written as a sum of two or fewer 11-smooth numbers (A051038).
0
479, 958, 1151, 1319, 1437, 1559, 1679, 1916, 2302, 2351, 2395, 2638, 2874, 2999, 3013, 3071, 3118, 3353, 3358, 3453, 3671, 3737, 3769, 3832, 3911, 3957, 4199, 4309, 4311, 4604, 4677, 4702, 4703, 4751, 4790, 4919, 5037, 5057, 5269, 5276, 5389, 5443, 5519, 5597, 5683
OFFSET
1,1
COMMENTS
Similar to A323046 (3-smooth), A323049 (5-smooth) or A323050 (7-smooth).
This sequence is a subsequence of A323046, A323049, and A323050.
Notice that A045535(4) = a(1) = 479.
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
See A323046 (3-smooth), A323049 (5-smooth) or A323050 (7-smooth). Cf. A051038, A045535 (or A062241).
Sequence in context: A122268 A186950 A056987 * A025025 A108256 A262222
KEYWORD
nonn
AUTHOR
Carlos Alves, Jan 03 2019
STATUS
approved