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.

A053201 Pascal's triangle (excluding first, last element of each row) read by rows, row n read mod n.

Original entry on oeis.org

0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 3, 2, 3, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 6, 0, 4, 0, 0, 0, 3, 0, 0, 3, 0, 0, 0, 5, 0, 0, 2, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 4, 3, 0, 0, 0, 3, 4, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 7, 0, 7, 2, 7, 0, 7, 0, 7, 0, 0, 0, 5, 0, 3, 10, 0, 0, 10, 3, 0, 5, 0
Offset: 2

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Author

Asher Auel, Dec 12 1999

Keywords

Comments

Prime numbered rows contain all zeros.

Examples

			0; 0,0; 0,2,0; 0,0,0,0; 0,3,2,3,0; ...
row 6 = 6 mod 6, 15 mod 6, 20 mod 6, 15 mod 6, 6 mod 6 = 0, 3, 2, 3, 0
		

Crossrefs

Row sums give A053205. Cf. A053200, A053202, A053203, A007318 (Pascal's triangle)
Cf. A053214 (central terms).

Programs

  • Haskell
    a053201 n k = a053201_tabl !! (n-2) !! (k-1)
    a053201_row n = a053201_tabl !! (n-2)
    a053201_tabl = zipWith (map . (flip mod)) [2..] a014410_tabl
    -- Reinhard Zumkeller, Aug 17 2013
  • Mathematica
    row[n_] := Table[ Mod[ Binomial[n, k], n], {k, 1, n-1}]; Table[row[n], {n, 2, 15}] // Flatten (* Jean-François Alcover, Aug 12 2013 *)

Formula

T(n,k) = A014410(n,k) mod n, k=1..n-1.

Extensions

a(62) and a(68) corrected by T. D. Noe, Feb 08 2008