OFFSET
1,2
LINKS
Ivan Neretin, Table of n, a(n) for n = 1..10000
EXAMPLE
There are three terms among the first 8 terms of the sequence which divide 9 (a(1)=1,a(3)=3,a(8)=9). So a(9) is the smallest multiple of 3 which does not occur among the first 8 terms of the sequence. 3,6 and 9 occur earlier in the sequence, so a(9) = 12.
MATHEMATICA
a = {1}; Do[AppendTo[a, Min[Complement[Range[Max[a] + 1]*Count[a, x_ /; Divisible[n, x]], a]]], {n, 2, 72}]; a (* Ivan Neretin, Sep 03 2015 *)
PROG
(PARI) S=Set([1]); for(n=2, 100, d=length(setintersect(S, Set(divisors(n)))); k=d; while(setsearch(S, k), k+=d); S=setunion(S, [k]); print1(k, ", "); ) \\ Max Alekseyev, Jun 02 2007
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Leroy Quet, Mar 09 2007
EXTENSIONS
More terms from Max Alekseyev, Jun 02 2007
STATUS
approved