A169852 a(n) = position of n in A169851.

2, 5, 3, 13, 4, 10, 8, 6, 1, 18, 7, 22, 9, 12, 15, 31, 16, 35, 14, 11, 17, 41, 20, 26, 21, 24, 28, 56, 25, 60, 29, 19, 30, 27, 33, 66, 34, 23, 38, 73, 37, 80, 39, 43, 40, 88, 44, 49, 45, 32, 46, 99, 47, 52, 48, 36, 55, 106, 51, 114, 59, 50, 63, 53, 58, 127, 64, 42, 54, 133, 62, 137, 65

Offset

2,1

Comments

A generalization of A064421.

Links

Robert Israel, Table of n, a(n) for n = 2..10000

Maple

N:= 100: V:= Vector(N): count:= 1: x:= 10: V[10]:= 1: Cands:= [$2..9, $11..1000]: nC:= nops(Cands):
for iter from 2 while count < N-1 do
  found:= false;
  for i from 1 to nC do
    if igcd(Cands[i], x) > 1 then
      x:= Cands[i];
      Cands:= subsop(i=NULL, Cands);
      found:= true;
      if x <= N then V[x]:= iter; count:= count+1;  fi;
      break;
     fi
  od;
  if not found then break fi
od:
convert(V[2..N], list); # Robert Israel, Dec 31 2024

Crossrefs

Sequence in context: A120858 A124937 A279342 * A318189 A176914 A194010

Adjacent sequences: A169849 A169850 A169851 * A169853 A169854 A169855

Keyword

nonn

Author

T. D. Noe and N. J. A. Sloane, Jun 02 2010

Status

approved