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.

A203155 (n-1)-st elementary symmetric function of {3, 3, 4, 4, 5, 5,..., Floor[(n+5)/2]}.

Original entry on oeis.org

1, 6, 33, 168, 984, 5640, 37440, 246240, 1853280, 13880160, 117391680, 989936640, 9315855360, 87500528640, 907925760000, 9408462336000, 106785133056000, 1210848984576000, 14928525545472000, 183922359312384000, 2448351304261632000
Offset: 1

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Author

Clark Kimberling, Dec 29 2011

Keywords

Examples

			Let esf abbreviate "elementary symmetric function".  Then
0th esf of {3}:  1
1st esf of {3,3}:  3+3=6
2nd esf of {3,3,4} is 3*3+3*4+3*4=33
		

Crossrefs

Programs

  • Mathematica
    f[k_] := Floor[(k + 5)/2]; t[n_] := Table[f[k], {k, 1, n}]
    a[n_] := SymmetricPolynomial[n - 1, t[n]]
    Table[a[n], {n, 1, 22}]  (* A203155 *)