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 A036690 Product of a prime and the following number. 8
 6, 12, 30, 56, 132, 182, 306, 380, 552, 870, 992, 1406, 1722, 1892, 2256, 2862, 3540, 3782, 4556, 5112, 5402, 6320, 6972, 8010, 9506, 10302, 10712, 11556, 11990, 12882, 16256, 17292, 18906, 19460, 22350, 22952, 24806, 26732, 28056, 30102 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The infinite sum over the reciprocals is given in A179119. - Wolfdieter Lang, Jul 10 2019 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 FORMULA a(n) = prime(n)*(prime(n)+1). a(n) = A060800(n) - 1. a(n) = 2*A034953(n). - Artur Jasinski, Feb 06 2007 EXAMPLE a(3)=30 because prime(3)=5 and prime(3)+1=6, hence 5*6 = 30. MATHEMATICA Table[(Prime[n] + 1) Prime[n], {n, 1, 100}] (* Artur Jasinski, Feb 06 2007 *) PROG (MAGMA)[p^2+p: p in PrimesUpTo(250)]; // Vincenzo Librandi, Dec 19 2010 (PARI) a(n)=my(p=prime(n)); p*(p+1) \\ Charles R Greathouse IV, Mar 27 2020 CROSSREFS Cf. A036689, A034953, A179119. Sequence in context: A071342 A125056 A011987 * A229746 A256579 A322374 Adjacent sequences:  A036687 A036688 A036689 * A036691 A036692 A036693 KEYWORD nonn,easy AUTHOR STATUS approved

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Last modified October 23 04:16 EDT 2020. Contains 337962 sequences. (Running on oeis4.)