A333993 Square spiral on a 2D square lattice, one term per cell, starting at the origin with 0; the integers forming a square of size k X k, for all k = 1, 2, 3, ..., add up to a number that does not contain the digit 1.

0, 2, 3, 4, 5, 20, 6, 7, 23, 8, 9, 22, 24, 25, 200, 26, 27, 28, 29, 203, 30, 33, 32, 202, 2000, 34, 35, 36, 205, 37, 38, 204, 39, 42, 2002, 40, 43, 90, 59, 84, 46, 2023, 44, 206, 53, 82, 48, 220, 284, 45, 57, 74, 207, 47, 85, 2244, 49, 52, 50, 76, 2043, 273, 20007, 436, 54, 55, 56, 58, 62, 60, 96

Offset: 1

Author

Eric Angelini and Jean-Marc Falcoz, Sep 04 2020

Keywords

• base
• nonn

Comments

This is the lexicographically earliest sequence of distinct nonnegative terms with this property. Computed in memory of Michaël Falcoz, Aug 20 2020.

Examples

			No integer in the spiral contains "1"; the integers forming any 2 X 2 square add up to a number without "1"; the integers forming any 3 X 3 square add up to a number without "1", etc.
The 5 X 5 square visible here (without the leg 34-35) is made of 25 terms summing up to 2968, a result that doesn't use the digit 1.
.
     30--33--32-202-2000-34
      |                   |
    203   6---7--23---8  35
      |   |           |   .
     29  20   0---2   9   .
      |   |       |   |   .
     28   5---4---3  22
      |               |
     27--26--200-25--24
.
		

Crossrefs

Cf. A337115.