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A334038
a(n) = Product_{p<=n, p prime} binomial(n,p).
1
1, 1, 1, 3, 24, 100, 1800, 15435, 702464, 13716864, 163296000, 1383574500, 109294479360, 3842829083808, 1159801183597056, 132320316074821875, 8213884352593920000, 327816138093181337600, 167079259535068179726336, 34044607357920579594754944
OFFSET
0,4
LINKS
EXAMPLE
For n=2, p=2: a(n) = C(2,2) = 1.
For n=3, p=2,3: a(n) = C(3,2) * C(3,3) = 3.
For n=4, p=2,3: a(n) = C(4,2) * C(4,3) = 24.
MAPLE
a:= n-> mul(`if`(isprime(p), binomial(n, p), 1), p=2..n):
seq(a(n), n=0..20); # Alois P. Heinz, Apr 13 2020
PROG
(PARI) a(n) = prod(k=1, n, if (isprime(k), binomial(n, k), 1)); \\ Michel Marcus, Apr 13 2020
(PARI) a(n)=my(s); forprime(p=2, n, s*=binomial(n, p)); s \\ Charles R Greathouse IV, Apr 13 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Om R. Patel, Apr 13 2020
STATUS
approved