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%I #12 May 08 2020 17:39:45
%S 5,19,29,139,251,12011,48619,51479,155117519,81676217699,
%T 1378465288199,5651707681619,386971244197199,1580132580471899,
%U 30067266499541039,6637553085023755473070799,35257120210449712895193719,399608854866744452032002440111
%N Primes of the form k$ - 1. Here '$' denotes the swinging factorial function (A056040).
%H Jinyuan Wang, <a href="/A163076/b163076.txt">Table of n, a(n) for n = 1..53</a>
%H Peter Luschny, <a href="/A180000/a180000.pdf">Die schwingende Fakultät und Orbitalsysteme</a>, August 2011.
%H Peter Luschny, <a href="http://www.luschny.de/math/primes/SwingingPrimes.html"> Swinging Primes.</a>
%e Since 4$ = 6 the prime 5 is listed.
%p a := proc(n) select(isprime, map(x -> A056040(x)-1,[$1..n])); sort(%) end:
%t Reap[Do[f = n!/Quotient[n, 2]!^2; If[PrimeQ[p = f - 1], Sow[p]], {n, 1, 70}]][[2, 1]] // Union (* _Jean-François Alcover_, Jun 28 2013 *)
%Y Cf. A055490, A056040, A163078 (arguments k), A163074, A163075.
%K nonn
%O 1,1
%A _Peter Luschny_, Jul 21 2009
%E More terms from _Jinyuan Wang_, Mar 22 2020
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