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A091995
Permutation of the natural numbers.
4
1, 2, 3, 4, 5, 7, 6, 8, 11, 9, 12, 16, 10, 13, 17, 22, 14, 18, 23, 29, 15, 19, 24, 30, 37, 20, 25, 31, 38, 46, 21, 26, 32, 39, 47, 56, 27, 33, 40, 48, 57, 67, 28, 34, 41, 49, 58, 68, 79, 35, 42, 50, 59, 69, 80, 92, 36, 43, 51, 60, 70, 81, 93, 106, 44, 52, 61, 71, 82, 94, 107
OFFSET
1,2
COMMENTS
Write the natural numbers as a triangle:
1
2...3
4...5...6
7...8...9..10
11..12..13..14..15
Now read off the numbers diagonally from upper-right to lower-left. 1 -> 2 -> 3 -> 4 -> 5 -> 7 -> 6 -> 8 -> 11 -> 9 -> 12 -> ...
CROSSREFS
a(n) = A090894(n-1)+1. Cf. A092180.
Sequence in context: A293052 A273751 A056017 * A343150 A338698 A361946
KEYWORD
easy,nonn
AUTHOR
Felix Tubiana, Mar 17 2004
STATUS
approved