A334038 a(n) = Product_{p<=n, p prime} binomial(n,p).

1, 1, 1, 3, 24, 100, 1800, 15435, 702464, 13716864, 163296000, 1383574500, 109294479360, 3842829083808, 1159801183597056, 132320316074821875, 8213884352593920000, 327816138093181337600, 167079259535068179726336, 34044607357920579594754944

Offset

0,4

Links

Alois P. Heinz, Table of n, a(n) for n = 0..145

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

Cf. A000040, A001142, A010051, A121497.

Sequence in context: A092780 A004282 A216725 * A320976 A164938 A342112

Adjacent sequences: A334035 A334036 A334037 * A334039 A334040 A334041

Keyword

nonn

Author

Om R. Patel, Apr 13 2020

Status

approved