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Numbers k such that k, k+2, k+4 are of the form p^2*q where p and q are distinct primes.
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%I #40 Jul 22 2021 02:08:42

%S 2523,2525,3175,22021,25529,28223,40325,53573,58923,73447,122571,

%T 132021,149675,152339,165175,172917,202221,209673,235825,267773,

%U 268223,308671,322223,371075,425723,430171,445923,488975,575973,591575

%N Numbers k such that k, k+2, k+4 are of the form p^2*q where p and q are distinct primes.

%C All terms are odd. See comment in A308736. - _Chai Wah Wu_, Jun 24 2019

%H Ray Chandler, <a href="/A308735/b308735.txt">Table of n, a(n) for n = 1..10000</a>

%e 3175 = 5 * 5 * 127,

%e 3177 = 3 * 3 * 353,

%e 3179 = 11 * 17 * 17.

%t psx = Table[{0}, {5}]; nmax = 600000; n = 1; lst = {};

%t While[n < nmax, n++;

%t psx = RotateRight[psx];

%t psx[[1]] = Sort[Last /@ FactorInteger[n]];

%t If[Union[{psx[[1]], psx[[3]], psx[[5]]}] == {{1, 2}},

%t AppendTo[lst, n - 4]];];

%t lst

%Y Cf. A074173, A308736.

%K nonn

%O 1,1

%A _Ray Chandler_, Jun 24 2019