cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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

Original entry on oeis.org

1, 1, 1, 3, 24, 100, 1800, 15435, 702464, 13716864, 163296000, 1383574500, 109294479360, 3842829083808, 1159801183597056, 132320316074821875, 8213884352593920000, 327816138093181337600, 167079259535068179726336, 34044607357920579594754944
Offset: 0

Views

Author

Om R. Patel, Apr 13 2020

Keywords

Examples

			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.
		

Crossrefs

Programs

  • 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
  • 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