OFFSET
0,3
EXAMPLE
The positive integers coprime to a(6)=8 are 1,3,5,7,9,11,13,15,17,19... The seventh of these is 13, so a(7) = 13.
MATHEMATICA
f[l_List] := Block[{k = 0, c = Length[l]}, While[c > 0, k++; While[ GCD[k, l[[ -1]]] > 1, k++ ]; c--; ]; Append[l, k]]; Nest[f, {1}, 70] (* Ray Chandler, Nov 11 2006 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Nov 08 2006
EXTENSIONS
Extended by Ray Chandler, Nov 11 2006
STATUS
approved