A162922 Square array read by antidiagonals: m is the a(n,m)th positive integer among those which are coprime to n. Or a(n,m) = 0 if m and n are not coprime.

1, 1, 2, 1, 0, 3, 1, 2, 2, 4, 1, 0, 0, 0, 5, 1, 2, 2, 3, 3, 6, 1, 0, 3, 0, 4, 0, 7, 1, 2, 0, 4, 3, 0, 4, 8, 1, 0, 3, 0, 0, 0, 5, 0, 9, 1, 2, 2, 4, 2, 5, 4, 6, 5, 10, 1, 0, 0, 0, 5, 0, 6, 0, 0, 0, 11, 1, 2, 2, 3, 3, 6, 3, 7, 5, 7, 6, 12, 1, 0, 3, 0, 4, 0

Offset

1,3

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

Rows 1 through 7 of the array:
n=1: 1,2,3,4,5,6,7,8,9,...
n=2: 1,0,2,0,3,0,4,0,5,...
n=3: 1,2,0,3,4,0,5,6,0,...
n=4: 1,0,2,0,3,0,4,0,5,...
n=5: 1,2,3,4,0,5,6,7,8,...
n=6: 1,0,0,0,2,0,3,0,0,...
n=7: 1,2,3,4,5,6,0,7,8,...

Maple

N:= 20: # for the first N antidiagonals
for n from 1 to N do
  t:= 0:
  for m from 1 to N+1-n do
    if igcd(m, n)=1 then
      t:= t+1; T[n, m]:= t;
    else T[n, m]:= 0
    fi
  od
od:
[seq(seq(T[i-m, m], m=1..i-1), i=1..N+1)]; # Robert Israel, Sep 05 2016

Crossrefs

Sequence in context: A182720 A347316 A146540 * A246180 A102057 A276276

Adjacent sequences: A162919 A162920 A162921 * A162923 A162924 A162925

Keyword

nonn,tabl

Author

Leroy Quet, Jul 17 2009

Extensions

More terms from Robert Israel, Sep 05 2016

Status

approved