OFFSET
1,2
COMMENTS
Sequence is likely a permutation of the positive integers.
LINKS
Ivan Neretin, Table of n, a(n) for n = 1..10000
EXAMPLE
3 is the largest integer which occurs among the first 5 terms of the sequence and which divides 6. So for a(6) we want the 3rd integer from among those positive integers not among the first 5 terms of the sequence (i.e. we want the 3rd integer from among 4,6,7,8,10,...). So a(6) = 7.
MATHEMATICA
f[l_List] := Block[{k = 0, c = Max @@ Select[l, Mod[Length[l] + 1, # ] == 0 &]}, While[c > 0, k++; While[MemberQ[l, k], k++ ]; c--; ]; Append[l, k]]; Nest[f, {1}, 72] (* Ray Chandler, Nov 23 2006 *)
Fold[Append[#1, Complement[Range[Max@#1 + (r = Max@Intersection[#1, Divisors@#2])], #1][[r]]] &, {1}, Range[2, 70]] (* Ivan Neretin, Oct 20 2018 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Nov 20 2006
EXTENSIONS
Extended by Ray Chandler, Nov 23 2006
STATUS
approved