|
|
A264411
|
|
a(n) = binomial(2*n^2, n).
|
|
1
|
|
|
1, 2, 28, 816, 35960, 2118760, 156238908, 13834413152, 1429702652400, 168899639028120, 22451004309013280, 3316276739861976176, 538884034480519066248, 95533608280955635872536, 18348499272339029224271680, 3795302872076181378439692480, 841141456821158064519401490400, 198852623925936212550698141090040, 49949550731916384239220134110005024
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
a(n) = Sum_{k=0..n} binomial(n^2, k) * binomial(n^2, n-k).
|
|
MATHEMATICA
|
|
|
PROG
|
(PARI) {a(n)=binomial(2*n^2, n)}
for(n=0, 15, print1(a(n), " "))
(PARI) {a(n)=sum(k=0, n, binomial(n^2, k)*binomial(n^2, n-k))}
for(n=0, 15, print1(a(n), " "))
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|