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 A239942 a(n) = 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. A000040, 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 April 21 03:11 EDT 2024. Contains 371850 sequences. (Running on oeis4.)