%I #52 Feb 19 2024 01:48:03

%S 8,12,20,28,44,52,68,76,92,116,124,148,164,172,188,212,236,244,268,

%T 284,292,316,332,356,388,404,412,428,436,452,508,524,548,556,596,604,

%U 628,652,668,692,716,724,764,772,788,796,844,892,908,916,932,956,964,1004,1028,1052,1076,1084,1108,1124,1132,1172,1228,1244,1252

%N Primes multiplied by 4.

%C Numbers k such that Sum_{d|k} (-1)^d = A048272(k) = 2. - _Benoit Cloitre_, Apr 14 2002

%H Paolo P. Lava, <a href="/A001749/b001749.txt">Table of n, a(n) for n = 1..20000</a>

%t 4 * Prime[Range[66]] (* _Vladimir Joseph Stephan Orlovsky_, Apr 29 2008 *)

%o (Haskell)

%o a001749 = (* 4) . a000040 -- _Reinhard Zumkeller_, Feb 20 2012

%o (PARI) a(n)=4*prime(n) \\ _Charles R Greathouse IV_, Mar 25 2014

%o (PARI) 4 * primes(66) \\ _Joerg Arndt_, Mar 26 2014

%o (Magma) [4*p: p in PrimesUpTo(300)]; // _Vincenzo Librandi_, Mar 26 2014

%Y Cf. A000040, A003415, A048272.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_