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A239942 Prime(n)! - prime(n - 1)!. 1
4, 114, 4920, 39911760, 6187104000, 355681201075200, 121289412980736000, 25851895093784567808000, 8841761967887685215658639360000, 8213996892184183115771019264000000, 13763753083003506392138056763855339520000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Michael De Vlieger, Table of n, a(n) for n = 2..87

FORMULA

a(n) = A039716(n) - A039716(n-1).

EXAMPLE

a(3) = Prime(3)! - Prime(2)! = 5! - 3! = 120 - 6 = 114.

MAPLE

A239942:=n->ithprime(n)!-ithprime(n-1)!: seq(A239942(n), n=2..15); # Wesley Ivan Hurt, Aug 03 2014

MATHEMATICA

a239942[n_Integer] := Prime[n]! - Prime[n - 1]!; Table[a239942[n], {n, 2, 87}] (* Michael De Vlieger, Aug 03 2014 *)

PROG

(Perl)

#!/usr/bin/perl

use strict;

use warnings;

use feature 'say';

use Math::Prime::XS qw(is_prime);

use Memoize;

use Math::BigInt;

memoize('factorial');

use Data::Dumper;

my @primes = ();

for (2 .. 200) {

        if(is_prime($_)) {

                push @primes, $_;

        }

}

for (1 .. $#primes) {

        say factorial($primes[$_]) - factorial($primes[$_ - 1]);

}

sub factorial {

        my $x = Math::BigInt->new(shift);

        return $x if $x == 1;

        return factorial($x - 1) * $x;

}

(PARI)  a(n)=prime(n)! - prime(n-1)!;

vector(22, n, a(n+1)) \\ Joerg Arndt, Mar 31 2014

(Python)

from gmpy2 import mpz, fac

from sympy import prime

def A239942(n):

....return fac(mpz(prime(n))) - fac(mpz(prime(n-1))) # Chai Wah Wu, Aug 06 2014

CROSSREFS

Cf. A039716.

Sequence in context: A194495 A260575 A275747 * A261457 A080482 A340277

Adjacent sequences:  A239939 A239940 A239941 * A239943 A239944 A239945

KEYWORD

nonn

AUTHOR

Norman Koch, Mar 29 2014

STATUS

approved

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Last modified May 16 06:43 EDT 2022. Contains 353693 sequences. (Running on oeis4.)