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A337116
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Spiral on a 2D square lattice, one term per cell, starting at the origin with 0; the four integers forming any 2 X 2 square add up to a prime.
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14
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0, 1, 2, 4, 3, 6, 5, 8, 10, 7, 11, 9, 12, 14, 17, 13, 15, 16, 18, 24, 19, 23, 25, 28, 22, 20, 30, 31, 32, 26, 21, 38, 33, 37, 34, 27, 29, 36, 40, 35, 50, 44, 39, 47, 42, 41, 43, 46, 49, 45, 53, 48, 54, 56, 59, 51, 52, 55, 65, 57, 64, 58, 60, 63, 61, 70, 62, 73, 75, 67
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OFFSET
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1,3
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COMMENTS
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This is (by definition) the lexicographically earliest permutation of the nonnegative integers with this property.
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LINKS
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EXAMPLE
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The four integers inside each of the four 2 X 2 squares that contain 0 sum up to a prime: 0+1+2+4=7 / 0+4+3+6=13 / 0+6+5+8=19 / 0+8+10+1=19. This is true for any 2 X 2 square picked up on the (infinite) grid: the upper right corner below sums up to the prime 79 for instance (22+20+30+7).
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19--23--25--28--22--20
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24 5---8--10---7 30
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18 6 0---1 11 .
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16 3---4---2 9 .
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15--13--17--14--12
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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