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%I #33 Jun 19 2023 17:08:23
%S 6,20,28,88,104,272,304,368,464,496,1184,1312,1376,1504,1696,1888,
%T 1952,4288,4544,4672,5056,5312,5696,6208,6464,6592,6848,6976,7232,
%U 8128,16768,17536,17792,19072,19328,20096,20864,21376,22144,22912,23168,24448,24704,25216
%N Primitive practical numbers of the form 2^i * prime(k).
%C Intersection of A267124 and A100368.
%C a(n) is a number of the form 2^i * prime(k) for i > 0 and A007053(i) < k <= A007053(i+1).
%C Terms are pseudoperfect numbers, A005835 and are also primitive pseudoperfect numbers, A006036.
%H Amiram Eldar, <a href="/A308710/b308710.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = 2^floor(log_2(prime(n+1))) * prime(n+1).
%t a[n_] := (p = Prime[n+1]) * 2^Floor[Log2[p]]; Array[a, 50] (* _Amiram Eldar_, Sep 22 2019 *)
%o (PARI) isok(n) = is_A100368(n) && is_A267124(n); \\ _Michel Marcus_, Jun 19 2019
%Y Cf. A000040, A000079, A005153, A005835, A006036, A007053, A100368, A267124.
%K nonn
%O 1,1
%A _Miko Labalan_, Jun 19 2019