A047742 A discrete analog of Li(n): a(n) = ceiling(Sum_{k=2..n} 1/log(k)).

2, 3, 4, 4, 5, 5, 6, 6, 7, 7, 7, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 12, 13, 13, 13, 13, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24

Offset

2,1

Links

Table of n, a(n) for n=2..69.

Mathematica

a[n_]:=Ceiling[Sum[1/Log[k], {k, 2, n}]]; Array[a, 68, 2] (* Stefano Spezia, May 29 2025 *)

Crossrefs

Cf. A047741.

Sequence in context: A093874 A047741 A047784 * A383236 A302778 A203967

Adjacent sequences: A047739 A047740 A047741 * A047743 A047744 A047745

Keyword

nonn

Author

N. J. A. Sloane

Status

approved