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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

Table of n, a(n) for n=1..5.

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.)