A169841 EKG sequence started at 5 instead of 2.

5, 10, 2, 4, 6, 3, 9, 12, 8, 14, 7, 21, 15, 18, 16, 20, 22, 11, 33, 24, 26, 13, 39, 27, 30, 25, 35, 28, 32, 34, 17, 51, 36, 38, 19, 57, 42, 40, 44, 46, 23, 69, 45, 48, 50, 52, 54, 56, 49, 63, 60, 55, 65, 70, 58, 29, 87, 66, 62, 31, 93, 72, 64, 68, 74, 37, 111, 75, 78, 76, 80, 82, 41

Offset: 1

Author

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

Keywords

• nonn

Links

• Peter Kagey, Table of n, a(n) for n = 1..10000

Crossrefs

For other initial terms, see A064413, A169837, A169839, A169843, A169845, A169847, A169849, A169851, A169853, A169855.

Cf. A169842.

Programs

Maple

N:= 1000: # for terms before the first term > N
V:= Vector(N):
A[1]:= 5: V[5]:= 1:
for n from 2 do
  S:= {seq(seq(k*p,k=1..N/p),p=numtheory:-factorset(A[n-1]))};
  for s in sort(convert(S,list)) do
    if V[s] = 0 then
      A[n]:= s;
      break
    fi
  od;
  if V[s] = 1 then break fi;
  V[s]:= 1;
od:
seq(A[i],i=1..n-1); # Robert Israel, Jan 18 2016