A163081 - OEIS

A163081

Primes of the form p$ + 1 where p is prime, where '$' denotes the swinging factorial (A056040).

%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