OFFSET
1,2
COMMENTS
a(n+1) - a(n) = A013939(n+1).
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
MATHEMATICA
A013939[n_] := Sum[Floor[n/Prime[k]], {k, 1, n}]; RecurrenceTable[{a[n] == a[n - 1] + A013939[n], a[1] == 1}, a, {n, 1, 50}] (* G. C. Greubel, May 20 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jun 22 2004
STATUS
approved