This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A060125 Self-inverse infinite permutation which shows the position of the inverse of each finite permutation in A060117 (or A060118) in the same sequence; or equally, the cross-indexing between A060117 and A060118. 18
 0, 1, 2, 5, 4, 3, 6, 7, 14, 23, 22, 15, 12, 19, 8, 11, 16, 21, 18, 13, 20, 17, 10, 9, 24, 25, 26, 29, 28, 27, 54, 55, 86, 119, 118, 87, 84, 115, 56, 59, 88, 117, 114, 85, 116, 89, 58, 57, 48, 49, 74, 101, 100, 75, 30, 31, 38, 47, 46, 39, 60, 67, 80, 107, 112, 93, 66, 61, 92 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS PermRank3Aux is a slight modification of rank2 algorithm presented in Myrvold-Ruskey article. LINKS Antti Karttunen, Table of n, a(n) for n = 0..5040 W. Myrvold and F. Ruskey, Ranking and Unranking Permutations in Linear Time, Inform. Process. Lett. 79 (2001), no. 6, 281-284. FORMULA a(n) = PermRank3L(PermUnrank3R(n)) or PermRank3R(PermUnrank3L(n)) or PermRank3L(convert(invperm(convert(PermUnrank3L(j), 'disjcyc')), 'permlist', nops(PermUnrank3L(j)))) MAPLE with(group); permul := (a, b) -> mulperms(b, a); swap := (p, i, j) -> convert(permul(convert(p, 'disjcyc'), [[i, j]]), 'permlist', nops(p)); PermRank3Aux := proc(n, p, q) if(1 = n) then RETURN(0); else RETURN((n-p[n])*((n-1)!) + PermRank3Aux(n-1, swap(p, n, q[n]), swap(q, n, p[n]))); fi; end; PermRank3R := p -> PermRank3Aux(nops(p), p, convert(invperm(convert(p, 'disjcyc')), 'permlist', nops(p))); PermRank3L := p -> PermRank3Aux(nops(p), convert(invperm(convert(p, 'disjcyc')), 'permlist', nops(p)), p); CROSSREFS Cf. A060117, A060118, A060126, A060127, A275957, A275958. Cf. A261220 (fixed points). Cf. A056019 (compare the scatter plots). Sequence in context: A128173 A265362 A264989 * A265361 A265357 A265358 Adjacent sequences:  A060122 A060123 A060124 * A060126 A060127 A060128 KEYWORD nonn,base,look AUTHOR Antti Karttunen, Mar 02 2001 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified July 15 14:39 EDT 2018. Contains 312638 sequences. (Running on oeis4.)