

A176049


Primes of the form n!*(n+1)!*(n+2)!  1 or n!*(n+1)!*(n+2)! + 1.


0




OFFSET

1,1


COMMENTS

Primes of the form A010790(k)1 or A010790(k)+1. This is the 3rd sequence in the supersequence whose first member is factorial primes, A002981 UNION A002982, and whose 2nd member is A176038 Primes of the form n!*(n+1)!  1 or n!*(n+1)! + 1.
a(9) has already 486 digits and is not listed for that reason. The sequence is generated by the nvalues 0, 1, 1, 4, 6, 9, 13, 19, 101, 196,... [From R. J. Mathar, Oct 03 2010]
a(9) also ends with 72 nines.  Harvey P. Dale, Jan 05 2013


LINKS

Table of n, a(n) for n=1..8.


EXAMPLE

a(2) = 11 because 1!*(1+1)!*(1+2)!  1 = 11 is prime. a(4) = 2073601 because 4!*(4+1)!*(4+2)! + 1 = 2073601 is prime. a(7) because 13!*(13+1)!*(13+2)!  1 = 709885457731229765106401279999999 is prime.


MATHEMATICA

Select[Union[Flatten[Times@@#+{1, 1}&/@Partition[Range[0, 30]!, 3, 1]]], PrimeQ] (* Harvey P. Dale, Jan 05 2013 *)


CROSSREFS

Cf. A000040, A000142, A002981, A002982, A010790, A176038.
Sequence in context: A105290 A201426 A158790 * A228237 A186078 A224857
Adjacent sequences: A176046 A176047 A176048 * A176050 A176051 A176052


KEYWORD

easy,nonn


AUTHOR

Jonathan Vos Post, Apr 07 2010


EXTENSIONS

a(8) from R. J. Mathar, Oct 03 2010


STATUS

approved



