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A054068
Permutation of N = set of natural numbers: a(n)+C(k,2), where a=A054065 and k=Floor((1+sqrt(8n-3))/2).
4
1, 3, 2, 5, 4, 6, 8, 10, 7, 9, 15, 12, 14, 11, 13, 20, 17, 19, 16, 21, 18, 26, 23, 28, 25, 22, 27, 24, 33, 30, 35, 32, 29, 34, 31, 36, 41, 38, 43, 40, 45, 37, 42, 39, 44, 50, 55, 47, 52, 49, 54, 46, 51, 48, 53, 60, 65, 57, 62, 59, 64, 56, 61
OFFSET
1,2
EXAMPLE
Referring to A054065, just add C(k,2) to the numbers in p(k): e.g. p(1)=(1)->(1); p(2)=(2,1)->(3,2); p(3)=(2,1,3)->(5,4,6).
CROSSREFS
Inverse permutation: A054069.
Sequence in context: A194904 A194876 A194837 * A194870 A355014 A302252
KEYWORD
nonn
STATUS
approved