A323046 Numbers that are neither 3-smooth nor a sum of two 3-smooth numbers.

23, 46, 47, 53, 61, 69, 71, 77, 79, 92, 94, 95, 101, 103, 106, 107, 115, 119, 121, 122, 125, 127, 133, 138, 139, 141, 142, 143, 149, 151, 154, 157, 158, 159, 161, 167, 169, 173, 175, 179, 181, 183, 184, 185, 187, 188, 190, 191, 197, 199, 202, 203, 205, 206, 207, 211, 212, 213, 214, 215, 221, 223, 227, 229, 230, 231, 233

Offset: 1

Author

Carlos Alves, Jan 03 2019

Keywords

• nonn

Examples

			23 is not in A003586; also 22 (23-1), 21 (23-2), 20 (23-3), 19 (23-2*2), 17 (23-2*3), 15 (23-2*2*2), 14 (23-3*3), 11 (23-2*2*3), 7 (23-2*2*2*2), 5 (23-2*3*3) are not in A003586.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A003586, A237442, A323047, A323049, A323050. Subsequence of A081329.

Programs

Maple

N:= 1000: # to get all terms <= N
S:= {seq(seq(2^i*3^j,i=0..ilog2(N/3^j)),j=0..floor(log[3](N)))}:
sort(convert({$1..N} minus S minus map(t -> op(map(`+`, S,t)), S), list)); # Robert Israel, May 19 2019