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A163077 Numbers n such that n$ + 1 is prime. Here '$' denotes the swinging factorial function (A056040). 3
0, 1, 2, 3, 4, 5, 8, 9, 14, 15, 24, 27, 31, 38, 44, 45, 49, 67, 76, 92, 99, 119, 124, 133, 136, 139, 144, 168, 171, 185, 265, 291, 332, 368, 428, 501, 631, 680, 689, 696, 765, 789, 890, 1034, 1233, 1384, 1517, 1615, 1634, 1809, 2632, 2762, 3925, 4419, 5108, 5426 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

REFERENCES

Peter Luschny, "Divide, swing and conquer the factorial and the lcm{1,2,...,n}", preprint, April 2008.

LINKS

Table of n, a(n) for n=1..56.

Peter Luschny, Swinging Primes.

EXAMPLE

0$ + 1 = 1 + 1 = 2 is prime, so 0 is in the sequence.

MAPLE

a := proc(n) select(x -> isprime(A056040(x)+1), [$0..n]) end:

MATHEMATICA

fQ[n_] := PrimeQ[1 + 2^(n - Mod[n, 2])*Product[k^((-1)^(k + 1)), {k, n}]]; Select[ Range[0, 8660], fQ] (* Robert G. Wilson v, Aug 09 2010 *)

CROSSREFS

Cf. A163078, A163079, A163080, A002981.

Sequence in context: A094103 A268359 A054181 * A204810 A240080 A194714

Adjacent sequences:  A163074 A163075 A163076 * A163078 A163079 A163080

KEYWORD

nonn

AUTHOR

Peter Luschny, Jul 21 2009

EXTENSIONS

a(45) - a(56) from Robert G. Wilson v, Aug 09 2010

STATUS

approved

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Last modified June 26 23:21 EDT 2017. Contains 288777 sequences.