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A163075 Primes of the form n$ + 1. Here '$' denotes the swinging factorial function (A056040). 4
2, 3, 7, 31, 71, 631, 3433, 51481, 2704157, 280816201, 4808643121, 35345263801, 2104098963721, 94684453367401, 1580132580471901, 483701705079089804581 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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..16.

Peter Luschny, Swinging Primes.

EXAMPLE

Since 3$ = 4$ = 6 the prime 7 is listed, however only once.

MAPLE

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

MATHEMATICA

Reap[Do[f = n!/Quotient[n, 2]!^2; If[PrimeQ[p = f + 1], Sow[p]], {n, 1, 70}]][[2, 1]] // Union (* Jean-Fran├žois Alcover, Jun 28 2013 *)

CROSSREFS

Cf. A163077 (arguments n), A163074, A163076, A088332.

Sequence in context: A008840 A268477 A156313 * A265113 A228171 A089359

Adjacent sequences:  A163072 A163073 A163074 * A163076 A163077 A163078

KEYWORD

nonn

AUTHOR

Peter Luschny, Jul 21 2009

STATUS

approved

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