A112819 Numbers k such that lcm(1,2,3,...,k)/15 equals the denominator of the k-th harmonic number H(k).

20, 24, 529, 530, 531, 532, 533, 534, 535, 536, 537, 538, 539, 540, 541, 542, 543, 544, 545, 546, 547, 548, 549, 550, 551, 552, 553, 554, 555, 556, 557, 558, 41889597, 41889598, 41889599, 41889600, 41889601, 41889602, 41889603, 41889604, 41889605, 41889606, 41889607

Offset: 1

Author

Robert G. Wilson v, Sep 17 2005

Keywords

• nonn

Comments

When 15 occurs in A110566.

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A002805, A003418, A110566.

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

Programs

Mathematica

a = h = 1; t = {}; Do[a = LCM[a, n]; h = h + 1/n; If[a/Denominator[h] == 15, AppendTo[t, n]], {n, 10^6}]; t

Extensions

Definition corrected by Jinyuan Wang, May 03 2020

More terms from Chai Wah Wu, Mar 18 2021