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A082002 Square array read by antidiagonals, alternating upwards and downwards: T(1, 1) = 1 and every other entry is the smallest number not already used that has a common factor with every number in its row and column, not including the 1. 7
1, 2, 3, 6, 12, 4, 8, 18, 10, 9, 15, 24, 14, 30, 16, 20, 36, 22, 42, 40, 21, 27, 28, 48, 54, 26, 45, 32, 34, 60, 50, 66, 70, 56, 72, 33, 39, 44, 78, 84, 80, 75, 38, 51, 46, 52, 69, 68, 90, 96, 98, 102, 88, 104, 57, 63, 76, 108, 110, 114, 105, 100, 120, 92, 117, 58, 62, 87, 126 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
This is the boustrophedon method of filling an array.
LINKS
EXAMPLE
1, 2, 4, 8, 14, 16, ...
3, 12, 18, 24, ...
6, 10, 20, ...
9, 30, ...
15 ...
CROSSREFS
Sequence in context: A144641 A358237 A294720 * A369899 A102779 A287109
KEYWORD
nonn,tabl
AUTHOR
Amarnath Murthy, Apr 05 2003
EXTENSIONS
More terms from David Wasserman, Jul 30 2004
STATUS
approved

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Last modified March 28 14:38 EDT 2024. Contains 371254 sequences. (Running on oeis4.)