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.

A211783 Rectangular array: R(n,k)=n^2+[(n^2)/2]+...+[(n^2)/k], where [ ]=floor, by antidiagonals.

Original entry on oeis.org

1, 4, 1, 9, 6, 1, 16, 13, 7, 1, 25, 24, 16, 8, 1, 36, 37, 29, 18, 8, 1, 49, 54, 45, 33, 19, 8, 1, 64, 73, 66, 51, 36, 20, 8, 1, 81, 96, 89, 75, 56, 38, 21, 8, 1, 100, 121, 117, 101, 82, 60, 40, 22, 8, 1, 121, 150, 148, 133, 110, 88, 63, 42, 23, 8, 1, 144, 181, 183
Offset: 0

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Author

Clark Kimberling, Apr 20 2012

Keywords

Comments

For n>=1, row n is a homogeneous linear recurrence sequence with palindromic recurrence coefficients in the sense described at A211701.
Row 1: A000290
Row 2: A032528
Row 3: A211784
R(n,n)=A118014(n,n)
The sequence approached as a limit of the rows is A175346: (1,8,23,50,87,140,...)

Examples

			Northwest corner:
1....4....9....16....25....36
1....6....13...24....37....54
1....7....16...29....35....66
1....8....18...33....51....75
1....8....19...36....56....82
1....8....20...38....60....88
1....8....21...40....63....93
		

Crossrefs

Programs

  • Mathematica
    f[n_, m_] := Sum[Floor[n^2/k], {k, 1, m}]
    TableForm[Table[f[n, m], {m, 1, 40}, {n, 1, 16}]]
    Flatten[Table[f[n + 1 - m, m], {n, 1, 14}, {m, 1, n}]]