A322759 - OEIS

A322759

Numerator of Product_{i=1..n, j=1..n, k=1..n, m=1..n} (i+j+k+m-2)/(i+j+k+m-3).

1, 2, 500, 406594944, 17946021496671970416, 266763232240477060473636852903291418, 1455102310580730414248044171189633697513044431339233543733641216

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

COMMENTS

The sequence of rationals A322759/A322760 is the natural successor to A000984 and A008793.

REFERENCES

Miklos Bona, editor, Handbook of Enumerative Combinatorics, CRC Press, 2015, page 576, line 3, with a=b=c=d=n.

LINKS

EXAMPLE

1, 2, 500/3, 406594944/25, 17946021496671970416/343, 266763232240477060473636852903291418/1701, ...

MAPLE

f4:=proc(n) local a, i, j, k, m;

a:=1;

for i from 1 to n do

for j from 1 to n do

for k from 1 to n do

for m from 1 to n do

a:=a*(i+j+k+m-2)/(i+j+k+m-3); od: od: od: od: a; end;

t1 := [seq(f4(n), n=0..12)];

CROSSREFS

KEYWORD

nonn,frac

AUTHOR

STATUS

approved