OFFSET
1,3
REFERENCES
V. Brun, Un procédé qui ressemble au crible d'Eratosthene, Analele Stiintifice Univ. "Al. I. Cuza", Iasi, Romania, Sect. Ia Matematica, 1965, vol. 11B, pp. 47-53.
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = k for Fl(k) <= n < Fl(k+1), where Fl(i) = A000960(i).
For all n >= 1, a(A000960(n)) = n. [From above.] - Antti Karttunen, Nov 23 2016
EXAMPLE
7 -> 7 - [7/2] = 7 - 3 = 4 -> 4 - [4/3] = 4 - 1 = 3 -> 3 - [3/4] = 3 - 0 = 3, which is now fixed, so a(7) = 3.
MAPLE
f:=proc(n) local i, j, k; k:=n; for i from 2 to 10000 do j := floor(k/i); if j < 1 then break; fi; k := k-j; od; k; end;
MATHEMATICA
a[n_] := (k = 2; FixedPoint[# - Floor[# / k++]&, n]); Table[a[n], {n, 1, 96}] (* Jean-François Alcover, Nov 15 2011 *)
PROG
(Haskell)
a100617 = f 2 where
f k x = if x' == 0 then x else f (k + 1) (x - x') where x' = div x k
-- Reinhard Zumkeller, Jul 01 2013, Sep 15 2011
(Scheme, with my IntSeq-library)
;; Antti Karttunen, Nov 23 2016
CROSSREFS
KEYWORD
nonn,nice
AUTHOR
N. J. A. Sloane, Dec 03 2004
STATUS
approved