A025492 Fixed point reached by iterating the Kempner function A002034 starting at n.

1, 2, 3, 4, 5, 3, 7, 4, 3, 5, 11, 4, 13, 7, 5, 3, 17, 3, 19, 5, 7, 11, 23, 4, 5, 13, 3, 7, 29, 5, 31, 4, 11, 17, 7, 3, 37, 19, 13, 5, 41, 7, 43, 11, 3, 23, 47, 3, 7, 5, 17, 13, 53, 3, 11, 7, 19, 29, 59, 5, 61, 31, 7, 4, 13, 11, 67, 17, 23, 7, 71, 3, 73, 37, 5, 19, 11, 13, 79, 3, 3, 41, 83, 7, 17

Offset: 1

Author

David W. Wilson

Keywords

• nonn
• nice

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A002034, A025493.

Programs

Haskell

a025492 n = fst $ until (uncurry (==)) (\(x,x') -> (a002034 x, x)) (n,0)
-- Reinhard Zumkeller, Mar 09 2012

Mathematica

k[n_] := (m=1; While[ !IntegerQ[m!/n], m++]; m); a[n_] := FixedPoint[k, n]; Table[ a[n], {n, 1, 85}] (* Jean-François Alcover, Mar 15 2012 *)