OFFSET
0,3
LINKS
Rémy Sigrist, Table of n, a(n) for n = 0..10000
Rémy Sigrist, C program for A127434
EXAMPLE
(0+9) is coprime to a(0)=1; (1+9) is coprime to a(1)=1; (2+9) is coprime to a(2)=2; (4+9) is coprime to a(4)=3, (6+9) is coprime to a(6)=4; and (8+9) is coprime to a(8)=4. These six cases are the only cases where (k+n) is coprime to a(k), for 0<=k<=8. So a(9) = 6.
MATHEMATICA
f[l_List] := Block[{n = Length[l]}, Append[l, Count[Table[GCD[k + n - 1, l[[k]]], {k, n}], 1]]]; Nest[f, {1}, 75] (* Ray Chandler, Jan 22 2007 *)
PROG
(C) See Links section.
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Jan 14 2007
EXTENSIONS
Extended by Ray Chandler, Jan 22 2007
STATUS
approved