A180267 - OEIS

%I #5 Mar 05 2017 10:56:01

%S 1,5544,148512,1211364,5301223200,67804092195840,128850876,

%T 8937268342895692800,4383026968320,2042765424,147107459292393600,

%U 40633707301699873935974400,17158084020,24300280368

%N Prime(2*n+1)!/(60*prime(2*n-1)!).

%C Oscillating sequence

%H Harvey P. Dale, <a href="/A180267/b180267.txt">Table of n, a(n) for n = 1..1000</a>

%e a(3)=prime(7)!/prime(5)!/60=355687428096000/39916800/60=148512

%t #[[2]]/(60*#[[1]])&/@Partition[Prime[Range[1,31,2]]!,2,1] (* _Harvey P. Dale_, Mar 05 2017 *)

%o (PARI) a(n)=prime(2*n+1)!/prime(2*n-1)!/60

%Y Cf. A178614

%K easy,nonn

%O 1,2

%A Graziano Aglietti (mg5055(AT)mclink.it), Aug 23 2010