A107764 - OEIS

%I #8 Sep 25 2020 05:52:45

%S 1,8,13,64,104,169,512,832,1352,2197,4096,6656,10816,17576,28561,

%T 32768,53248,86528,140608,228488,262144,371293,425984,692224,1124864,

%U 1827904,2097152,2970344,3407872,4826809,5537792,8998912,14623232,16777216

%N Numbers of the form (8^i)*(13^j), with i, j >= 0.

%H Amiram Eldar, <a href="/A107764/b107764.txt">Table of n, a(n) for n = 1..10000</a>

%F Sum_{n>=1} 1/a(n) = (8*13)/((8-1)*(13-1)) = 26/21. - _Amiram Eldar_, Sep 25 2020

%F a(n) ~ exp(sqrt(2*log(8)*log(13)*n)) / sqrt(104). - _Vaclav Kotesovec_, Sep 25 2020

%t n = 10^6; Flatten[Table[8^i*13^j, {i, 0, Log[8, n]}, {j, 0, Log[13, n/8^i]}]] // Sort (* _Amiram Eldar_, Sep 25 2020 *)

%Y Cf. A025633, A025634, A107326, A107364, A107462, A107466, A107710, A108056, A108090.

%K nonn,easy

%O 1,2

%A Douglas Winston (douglas.winston(AT)srupc.com), Jun 11 2005