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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.

A269780 Table read by antidiagonals where T(i,j) is the location of the pair (i,j) in A269501.

Original entry on oeis.org

1, 2, 4, 5, 3, 9, 10, 8, 7, 16, 17, 15, 6, 14, 25, 26, 24, 13, 12, 23, 36, 37, 35, 22, 11, 21, 34, 49, 50, 48, 33, 20, 19, 32, 47, 64, 65, 63, 46, 31, 18, 30, 45, 62, 81, 82, 80, 61, 44, 29, 28, 43, 60, 79, 100, 101, 99, 78, 59, 42, 27, 41, 58, 77, 98, 121, 122, 120, 97, 76, 57, 40, 39, 56, 75, 96, 119, 144
Offset: 1

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Comments

This is trivially a permutation of the positive integers.
The "location" of the pair is taken to be the index of the second element of the pair.

Examples

			The table starts:
   1,  2,  5, 10, 17, 26
   4,  3,  8, 15, 24, 35
   9,  7,  6, 13, 22, 33
  16, 14, 12, 11, 20, 31
  25, 23, 21, 19, 18, 29
  36, 34, 32, 30, 28, 27
		

Crossrefs

Cf. A269501, A097292, A002522 (top row, left shifted).
If 1 is subtracted from each term we get A316323.

Formula

T(i,j) :=
if i=1, then (j-1)^2 + 1,
if i>j, then i^2 - 2j + 2,
and otherwise j^2 - 2i + 3.