%I #10 May 08 2020 17:38:05
%S 2,3,7,31,71,631,3433,51481,2704157,280816201,4808643121,35345263801,
%T 2104098963721,94684453367401,1580132580471901,483701705079089804581,
%U 6892620648693261354601,410795449442059149332177041,2522283613639104833370312431401
%N Primes of the form k$ + 1. Here '$' denotes the swinging factorial function (A056040).
%H Jinyuan Wang, <a href="/A163075/b163075.txt">Table of n, a(n) for n = 1..50</a>
%H Peter Luschny, <a href="/A180000/a180000.pdf">Die schwingende Fakultät und Orbitalsysteme</a>, August 2011.
%H Peter Luschny, <a href="http://www.luschny.de/math/primes/SwingingPrimes.html"> Swinging Primes.</a>
%e Since 3$ = 4$ = 6 the prime 7 is listed, however only once.
%p a := proc(n) select(isprime, map(x -> A056040(x)+1,[$1..n])) 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. A056040, A088332, A163077 (arguments k), A163074, A163076.
%K nonn
%O 1,1
%A _Peter Luschny_, Jul 21 2009
%E More terms from _Jinyuan Wang_, Mar 22 2020