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 A001749 Primes multiplied by 4. 21
 8, 12, 20, 28, 44, 52, 68, 76, 92, 116, 124, 148, 164, 172, 188, 212, 236, 244, 268, 284, 292, 316, 332, 356, 388, 404, 412, 428, 436, 452, 508, 524, 548, 556, 596, 604, 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers k such that Sum_{d|k} (-1)^d = A048272(k) = 2. - Benoit Cloitre, Apr 14 2002 Solutions of k'=k+4, where k' is the arithmetic derivative of k. - Paolo P. Lava, Feb 02 2012 LINKS Paolo P. Lava, Table of n, a(n) for n = 1..20000 MATHEMATICA 4 * Prime[Range[66]] (* Vladimir Joseph Stephan Orlovsky, Apr 29 2008 *) PROG (Haskell) a001749 = (* 4) . a000040  -- Reinhard Zumkeller, Feb 20 2012 (PARI) a(n)=4*prime(n) \\ Charles R Greathouse IV, Mar 25 2014 (PARI) 4 * primes(66) \\ Joerg Arndt, Mar 26 2014 (Magma) [4*p: p in PrimesUpTo(300)]; // Vincenzo Librandi, Mar 26 2014 CROSSREFS Cf. A000040, A003415, A048272. Sequence in context: A084488 A337877 A211410 * A175786 A258848 A072843 Adjacent sequences:  A001746 A001747 A001748 * A001750 A001751 A001752 KEYWORD nonn,easy AUTHOR STATUS approved

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Last modified August 15 20:27 EDT 2022. Contains 356148 sequences. (Running on oeis4.)