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A001749 revision #47

A001749

Primes multiplied by 4.

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

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OFFSET

1,1

COMMENTS

Numbers k such that Sum_{d|k} (-1)^d = A048272(k) = 2. - Benoit Cloitre, Apr 14 2002

Solutions of the differential equation 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)