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 A280318 a(n) is the n-th permutation generated by Heap's algorithm, represented by row number of A055089. 2
 0, 1, 3, 2, 4, 5, 11, 10, 8, 9, 7, 6, 12, 13, 15, 14, 16, 17, 23, 22, 20, 21, 19, 18, 93, 92, 94, 95, 90, 91, 78, 79, 81, 80, 82, 83, 89, 88, 86, 87, 85, 84, 74, 75, 73, 72, 77, 76, 52, 53, 48, 49, 51, 50, 71, 70, 68, 69, 67, 66, 55, 54, 59, 58 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS This is a permutation of the nonnegative integers. It divides naturally in sections of factorial length, so it can be seen as a triangle with row lengths A094258: 0, 1, 3, 2, 4, 5, 11, 10, 8, 9, 7, 6, 12, 13, 15, 14, 16, 17, 23, 22, 20, 21, 19, 18... Compare A280319 for Steinhaus-Johnson-Trotter algorithm, which is a triangle of finite permutations rather than one infinite permutation. LINKS Tilman Piesk, Table of n, a(n) for n = 0..5039 Tilman Piesk, Calculation in Python Wikipedia, Heap's algorithm EXAMPLE Example for the first 24 entries of the sequence. On the right are the permutations of {1,2,3,4} in the order generated by the Heap's algorithm:    n    rev colex        a(n)   Heap's    0     1 2 3 4          0     1 2 3 4    1     2 1 3 4          1     2 1 3 4    2     1 3 2 4          3     3 1 2 4    3     3 1 2 4          2     1 3 2 4    4     2 3 1 4          4     2 3 1 4    5     3 2 1 4          5     3 2 1 4    6     1 2 4 3         11     4 2 1 3    7     2 1 4 3         10     2 4 1 3    8     1 4 2 3          8     1 4 2 3    9     4 1 2 3          9     4 1 2 3   10     2 4 1 3          7     2 1 4 3   11     4 2 1 3          6     1 2 4 3   12     1 3 4 2         12     1 3 4 2   13     3 1 4 2         13     3 1 4 2   14     1 4 3 2         15     4 1 3 2   15     4 1 3 2         14     1 4 3 2   16     3 4 1 2         16     3 4 1 2   17     4 3 1 2         17     4 3 1 2   18     2 3 4 1         23     4 3 2 1   19     3 2 4 1         22     3 4 2 1   20     2 4 3 1         20     2 4 3 1   21     4 2 3 1         21     4 2 3 1   22     3 4 2 1         19     3 2 4 1   23     4 3 2 1         18     2 3 4 1 CROSSREFS Cf. A055089, A094258, A280319. Sequence in context: A059320 A255167 A264993 * A246982 A258215 A319073 Adjacent sequences:  A280315 A280316 A280317 * A280319 A280320 A280321 KEYWORD nonn,tabf AUTHOR Tilman Piesk, Dec 31 2016 STATUS approved

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Last modified August 19 07:06 EDT 2019. Contains 326115 sequences. (Running on oeis4.)