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 A100015 Subfactorial primes: primes of the form !n + 1 or !n - 1. Subfactorial or rencontres numbers or derangements !n = A000166. 2
 2, 3, 43, 481066515733, 130850092279663 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES R. A. Brualdi and H. J. Ryser: Combinatorial Matrix Theory, 1992, Section 7.2, p. 202. H. J. Ryser, Combinatorial Mathematics. Mathematical Association of America, Carus Mathematical Monograph 14, 1963, p. 23. LINKS R. M. Dickau, Derangement diagrams. H. Fripertinger, The Recontre Numbers, an online calculator. Mehdi Hassani, Derangements and Applications, Journal of Integer Sequences, Vol. 6 (2003), #03.1.2 EXAMPLE a(5) = 130850092279663 because the 5th subfactorial prime is !17 - 1 = 130850092279664 - 1 = 130850092279663. a(1) = 2 because !0 = !2 = 1, so !0 + 1 = !2 + 1 = 2. CROSSREFS Cf. A000166. Sequence in context: A062581 A077520 A230061 * A317672 A042819 A218002 Adjacent sequences:  A100012 A100013 A100014 * A100016 A100017 A100018 KEYWORD nonn AUTHOR Jonathan Vos Post, Nov 18 2004 STATUS approved

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Last modified December 15 09:05 EST 2019. Contains 329995 sequences. (Running on oeis4.)