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%I #25 Sep 21 2024 15:17:45
%S 4,18,600,35280,439084800,80951270400,6046686277632000,
%T 2311256907767808000,594596384994354462720000,
%U 256411097818451356681764864000000,254907998279515607349492449280000000,509258864375374766713691244518493388800000000,1371553591139716091434972544191070818271232000000000
%N a(n) = p*p! where p = prime(n).
%D Originally published on Nov 09 2004 by indiejade(AT)gmail.com
%F a(n) = A000040(n)*A039716(n). - _Michel Marcus_, Feb 08 2015
%F a(n) = A001563(A000040(n)). - _Michel Marcus_, Aug 04 2015
%e 2 * 2! = 4, 3 * 3! = 18, 5 * 5! = 600.
%t Array[Prime[#] Prime[#]! &, 13] (* _Michael De Vlieger_, Aug 04 2015 *)
%t #*#!&/@Prime[Range[15]] (* _Harvey P. Dale_, Sep 21 2024 *)
%o (Magma) [p*Factorial(p): p in PrimesUpTo(50)]; // _Vincenzo Librandi_, Jun 09 2013
%o (Python)
%o from sympy import factorial, prime
%o def a(n): p = prime(n); return p * factorial(p)
%o print([a(n) for n in range(1, 14)]) # _Michael S. Branicky_, Apr 18 2021
%Y Cf. A000040 (prime(n)), A039716 (prime(n)!).
%K nonn
%O 1,1
%A L. Shawnee Cook (shawneecook(AT)gmail.com), Feb 17 2006