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%I #9 May 08 2020 17:49:27
%S 3,7,31,4808643121,483701705079089804581,
%T 3283733939424401442167506310317720418331001
%N Primes of the form p$ + 1 where p is prime, where '$' denotes the swinging factorial (A056040).
%C The values of p are 2, 3, 5, 31, 67, 139 which is A163079. Subsequence of A163075 (primes of the form k$ + 1).
%H Jinyuan Wang, <a href="/A163081/b163081.txt">Table of n, a(n) for n = 1..7</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 3 and 3$ + 1 = 7 are prime, so 7 is a member.
%p a := proc(n) select(isprime,[$2..n]); select(isprime, map(x -> A056040(x)+1,%)) end:
%Y Cf. A056040, A103319, A163074-A163083.
%K nonn
%O 1,1
%A _Peter Luschny_, Jul 21 2009
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