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A128754 Permutation of positive integers obtained by swapping n-th natural number with the (n-g)-th sequentially, where g=prime(n+1)-prime(n)-1. 9
4, 3, 6, 9, 8, 11, 1, 2, 12, 15, 16, 13, 18, 7, 5, 21, 30, 23, 22, 17, 19, 25, 10, 27, 34, 29, 32, 31, 20, 24, 36, 37, 42, 39, 46, 47, 33, 26, 35, 41, 44, 43, 28, 53, 48, 51, 50, 49, 62, 55, 56, 61, 66, 38, 14, 59, 52, 45, 68, 63, 40, 67, 64, 57, 72, 71, 70, 73, 74, 77, 80, 79 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
By numerical explorations up to 50k terms, it seems to be an "infinite braid", i.e. it consists of a single infinite cycle, without any fixed points or closed cycles.
LINKS
PROG
(PARI) {pperm(n)= /* Returns a vector with n terms of the sequence */
local(m, q, v, x, j, ap); j=n+prime(n+6)-prime(n); v=vector(j); x=vector(n);
for(i=1, j, v[i]=i); for(i=1, j, ap=prime(i+1)-prime(i)-1; q=v[i]; v[i]=v[i-ap]; v[i-ap]=q);
for(i=1, n, x[i]=v[i]); return(x)}
CROSSREFS
Inverse of A128755, Cf. A128756, A128757.
Sequence in context: A305581 A016702 A198610 * A353401 A196889 A005522
KEYWORD
nonn
AUTHOR
Ferenc Adorjan (fadorjan(AT)freemail.hu or ferencadorjan(AT)gmail.com), Mar 24 2007
STATUS
approved

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Last modified July 8 04:08 EDT 2024. Contains 374149 sequences. (Running on oeis4.)