A372284 - OEIS

%I #12 May 11 2024 21:58:24

%S 2,3,5,11,7,31,13,19,17,37,29,41,47,59,23,97,53,829,71,149,101,167,79,

%T 151,43,103,157,113,139,109,137,197,353,89,277,293,269,229,73,61,571,

%U 83,191,691,251,179,127,257,193,173,239,163,331,613,617,311,67,523

%N Primes in the order in which they appear in A124652.

%C Analogous to A111239, a sequence which instead pertains to A109890.

%H Michael De Vlieger, <a href="/A372284/b372284.txt">Table of n, a(n) for n = 1..2500</a>

%e Let b(x) = A372009(x).

%e Table of first terms:

%e    n  b(n) a(n)

%e   -------------

%e    1    2    2

%e    2    3    3

%e    3    5    5

%e    4   11   11

%e    5   12    7

%e    6   20   31

%e    7   24   13

%e    8   28   19

%e    9   29   17

%e   10   33   37

%e   11   42   29

%e   12   43   41

%e   ...

%t nn = 300; c[_] := False;

%t rad[x_] := rad[x] = Times @@ FactorInteger[x][[All, 1]];

%t f[x_] := Select[Range[x], Divisible[x, rad[#]] &];

%t Array[Set[{a[#], c[#]}, {#, True}] &, 2]; s = a[1] + a[2];

%t {2}~Join~Reap[Do[r = f[s]; k = SelectFirst[r, ! c[#] &];

%t     If[PrimeQ[k], Sow[k]]; c[k] = True;

%t     s += k, {i, 3, nn}] ][[-1, 1]]

%Y Cf. A124652, A372009.

%K nonn

%O 1,1

%A _Michael De Vlieger_, Apr 29 2024