OFFSET
1,1
LINKS
FORMULA
(k+3*sqrt(k)) / k > = 1, (k+3*sqrt(k)) / k < 2 <=> k >=10, a(n) = 4 if n=1, a(n) = 2n + 3 if 2 <= n <= 9, a(n) = n + 12 if n>=10.
MAPLE
for n from 1 to 100 do: s:=0: for k from 1 to n do: s:=s+floor((k+3*sqrt(k))/k) : od:print(s):od:
MATHEMATICA
Accumulate[Table[Floor[(k+3*Sqrt[k])/k], {k, 70}]] (* Harvey P. Dale, Apr 27 2022 *)
PROG
(PARI) a(n)=if(n>8, n+12, 2*n+3-(n==1)) \\ Charles R Greathouse IV, Oct 27 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Michel Lagneau, Mar 28 2010
STATUS
approved