|
| |
|
|
A089130
|
|
Primes of the form (n!+2)/2.
|
|
45
| | |
|
|
|
OFFSET
| 1,1
|
|
|
LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..13
|
|
|
MATHEMATICA
| s=""; For[i=1, i<5^2, If[PrimeQ[(i!+2)/2], s=s<>ToString[(i!+2)/2]<>", "]; i++ ]; Print[s] (from Vladimir Orlovsky (4vladimir(AT)gmail.com), Apr 29 2008)
Select[Table[(n!+2)/2, {n, 0, 100}], PrimeQ] (* Vincenzo Librandi, Dec 07 2011 *)
|
|
|
PROG
| (PARI) nfactp2d2(n) = { for(x=1, n, y=floor((x!+ 2)/2); if(isprime(y), print1(y", ")) ) }
(MAGMA) [ a: n in [1..50] | IsPrime(a) where a is (Factorial(n)+2) div 2 ];
|
|
|
CROSSREFS
| Cf. A082672.
Sequence in context: A042061 A187560 A205532 * A081340 A127531 A037745
Adjacent sequences: A089127 A089128 A089129 * A089131 A089132 A089133
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Cino Hilliard (hillcino368(AT)gmail.com), Dec 05 2003
|
| |
|
|
