%I #11 Apr 08 2021 07:19:08

%S 38272753,38272754,38272755,38272756,38272757,38272758,38272759,

%T 38272760,38272761,38272762,38272763,38272764,38272765,38272766,

%U 38272767,38272768,38272769,38272770,38272771,38272772,38272773,38272774,38272775,38272776,38272777,38272778

%N Numbers k such that lcm(1,2,3,...,k)/21 equals the denominator of the k-th harmonic number H(k).

%C Positions where 21 occurs in A110566.

%H Chai Wah Wu, <a href="/A342350/b342350.txt">Table of n, a(n) for n = 1..10000</a>

%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/NonRecursions.html">Non Recursions</a>

%Y Cf. A002805, A003418, A110566.

%Y Cf. A098464, A112813, A112814, A112815, A112816, A112817, A112818, A112819, A112820, A112821, A112822.

%K nonn

%O 1,1

%A _Chai Wah Wu_, Mar 17 2021