A123367 a(n) = (n! - 2^n)/8, n >= 4.

1, 11, 82, 614, 5008, 45296, 453472, 4989344, 59874688, 778376576, 10897284352, 163459291904, 2615348727808, 44460928495616, 800296713183232, 15205637551038464, 304112751021948928, 6386367771463417856, 140500090972200435712, 3231502092360621031424

Offset: 4

Author

Aminu Alhaji Ibrahim, Oct 12 2006

Keywords

• nonn

Links

• G. C. Greubel, Table of n, a(n) for n = 4..448

Crossrefs

Cf. A123642.

Programs

Magma

[(Factorial(n)-2^n)/8: n in [4..25]]; // G. C. Greubel, Oct 13 2017

Mathematica

Table[(n!-2^n)/8,{n,4,30}] (* Harvey P. Dale, Aug 19 2012 *)

PARI

for(n=4,25, print1((n!-2^n)/8, ", ")) \\ G. C. Greubel, Oct 13 2017

Extensions

Corrected and extended by Harvey P. Dale, Aug 19 2012