OFFSET
0,2
COMMENTS
This sequence is in reply to an extension request made in A100449.
Note that gcd(0,m) = m for any m.
LINKS
Robert Price, Table of n, a(n) for n = 0..400
MATHEMATICA
f[n_] := Length[Complement[Union[Flatten[Table[If[i + j <= n && GCD[i, j] <= 1, {i, j}], {i, 0, n}, {j, 0, n}], 1]], {Null}]]; Table[f[n], {n, 0, 100}]
PROG
(PARI) alist(N) = my(c=2); vector(N, i, if(1==i, 1, c+=eulerphi(i-1))); \\ Ruud H.G. van Tol, Jul 09 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Robert Price, May 09 2013
STATUS
approved