A133706 Numerator of a remarkable product.

1, 2, 3, 4, 5, 6, 8, 16, 60, 440, 6028, 144672, 5726600, 355049200, 33019575600, 4442233570720, 838471586473400, 216325669310137200, 74596301633778977800, 33717528338468097965600, 19638774380740743660063720

Offset

1,2

Comments

The first nonintegral term occurs at n=76.

Links

Olivier Gérard, Table of n, a(n) for n = 1..100

Formula

a(n) = numerator(Product_{i=1..n-1} (394 - 225*i + 85*i^2 - 15*i^3 + i^4)/120).

Mathematica

a[n_]:= Numerator[Product[(394-225 i+85 i^2 -15 i^3+i^4)/120, {i, n-1 }]]; Array[a, 21] (* Stefano Spezia, Feb 08 2025 *)

Crossrefs

Sequence of denominators is in A133707.

Sequence in context: A048332 A249158 A119336 * A081710 A373933 A364455

Adjacent sequences: A133703 A133704 A133705 * A133707 A133708 A133709

Keyword

nonn,frac,changed

Author

Olivier Gérard, Sep 20, 2007

Status

approved