A039716 a(n) = prime(n)!.

2, 6, 120, 5040, 39916800, 6227020800, 355687428096000, 121645100408832000, 25852016738884976640000, 8841761993739701954543616000000, 8222838654177922817725562880000000, 13763753091226345046315979581580902400000000, 33452526613163807108170062053440751665152000000000

Offset: 1

Author

Labos Elemer

Keywords

• nonn
• easy
• nice

Comments

Subsequence of A000142.

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..88

Crossrefs

Cf. A000040, A000142, A100124, A177946.

Programs

Magma

[Factorial(NthPrime(n)): n in [1..20]]; // Vincenzo Librandi, Apr 21 2014

Maple

A039716 := proc(n)
    ithprime(n)! ;
end proc:
seq(A039716(n),n=1..10) ; # R. J. Mathar, Aug 01 2014

Mathematica

Table[Prime[n]!,{n,1,8}] (* Vladimir Joseph Stephan Orlovsky, Apr 27 2008 *)

PARI

a(n)=prime(n)! \\ Charles R Greathouse IV, Feb 07 2012

Sage

BB = primes_first_n(14)
L = []
for i in range(13):
    L.append(factorial(BB[i]))
L # Zerinvary Lajos, May 14 2007

Formula

a(n) = A000142(A000040(n)).

a(n) = A177946(n)*A000142(n). - Reinhard Zumkeller, May 15 2010

Sum_{n>=1} 1/a(n) = A100124. - Amiram Eldar, Nov 13 2020