A025626 - OEIS

%I #15 Sep 25 2020 05:00:30

%S 1,6,7,36,42,49,216,252,294,343,1296,1512,1764,2058,2401,7776,9072,

%T 10584,12348,14406,16807,46656,54432,63504,74088,86436,100842,117649,

%U 279936,326592,381024,444528,518616,605052,705894,823543,1679616,1959552

%N Numbers of form 6^i*7^j, with i, j >= 0.

%H Amiram Eldar, <a href="/A025626/b025626.txt">Table of n, a(n) for n = 1..10000</a>

%F Sum_{n>=1} 1/a(n) = (6*7)/((6-1)*(7-1)) = 7/5. - _Amiram Eldar_, Sep 25 2020

%F a(n) ~ exp(sqrt(2*log(6)*log(7)*n)) / sqrt(42). - _Vaclav Kotesovec_, Sep 25 2020

%t n = 10^6; Flatten[Table[6^i*7^j, {i, 0, Log[6, n]}, {j, 0, Log[7, n/6^i]}]] // Sort (* _Amiram Eldar_, Sep 25 2020 *)

%Y Cf. A025610, A025622, A025627, A025628, A025629.

%Y Cf. A025619, A025631, A025632, A003591, A003594, A003595, A036566.

%K easy,nonn

%O 1,2

%A _David W. Wilson_