OFFSET
1,4
COMMENTS
Conjecture: a(n+1)/a(n) converges to 1.39...
This constant is probably exp(1/3) = 1.395612425086089528628..., see A004080. - Ralf Stephan, Jun 03 2013
EXAMPLE
a(10) = 16 because 1 + 1/2 + ... + 1/15 < 10/3 < 1 + 1/2 + ... + 1/16.
MATHEMATICA
z = 32; f[n_] := 1/n; Do[s = 0; a[n] = NestWhile[# + 1 &, 1, ! (s += f[#]) >= n/3 &], {n, 1, z}]; m = Map[a, Range[z]]
PROG
(PARI) a(n)=local(s, k); s=0; k=1; while(s<=n/3, s=s+1/k; k++); k-1
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 30 2013
EXTENSIONS
More terms from Jean-François Alcover, Jun 05 2013
Deleted obsolete b-file. - N. J. A. Sloane, Jan 04 2019
STATUS
approved