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.

A088438 A chaotic Cantor integer type product set of the factorial function that trifurcates.

Original entry on oeis.org

2, 6, 4, 7, 24, 35, 8, 18, 70, 88, 12, 29, 140, 165, 16, 40, 234, 266, 20, 52, 352, 391, 24, 64, 494, 540, 28, 76, 660, 713, 32, 88, 850, 910, 36, 99, 1064, 1131, 40, 111, 1302, 1376, 44, 123, 1564, 1645, 48, 135, 1850, 1938, 52, 147, 2160, 2255, 56, 159, 2494
Offset: 0

Views

Author

Roger L. Bagula, Nov 09 2003

Keywords

Comments

This result is due to analysis of the prime product, composite product and factorial type function to a more general type of function: n!=Product[Set1[i],{i, limit1, limit2}]*Product[Set2[i],{i,limit3,limit4}] In this case the second product contains two intervals instead of one.

Crossrefs

Cf. A088140.

Programs

  • Mathematica
    (* factorial based function with half interval Cantor hole in the middle*) p[n_]=n!/Product[i, {i, n-Floor[n/4], n-Floor[3*n/4]}] digits=200 a0=Table[Floor[p[n]/p[n-1]], {n, 2, digits}]

Formula

P[n]=n!/Product[i, {i, n-Floor[n/4], n-Floor[3*n/4]}] a(n) = Floor[P[n]/P[n-1]]