OFFSET
1,3
COMMENTS
If a(n-1) = 1, then a(n) = n-1, obviously.
EXAMPLE
a(13)= 12. So a(14) = the number of terms among the first 13 terms which are divisible by the largest prime dividing 12 (which is 3).
a(7)=3 and a(13) = 12 are the two terms each divisible by 3, so a(14) = 2.
MAPLE
A006530 := proc(n) local ifs, i ; if n <= 3 then n ; else ifs := ifactors(n)[2] ; max( seq(op(1, i), i=ifs)) ; fi ; end: A118291 := proc(n) local a, anxt, i ; a := [1, 1] ; while nops(a) < n do anxt := 0 ; for i in a do if i mod A006530(op(-1, a)) = 0 then anxt := anxt+1 ; fi ; od: a := [op(a), anxt] ; od; a ; end: A118291(200) ; # R. J. Mathar, Sep 06 2007
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Apr 22 2006
EXTENSIONS
More terms from R. J. Mathar, Sep 06 2007
STATUS
approved