login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A307266 Row 8 of array in A059897. 2
8, 4, 24, 2, 40, 12, 56, 1, 72, 20, 88, 6, 104, 28, 120, 128, 136, 36, 152, 10, 168, 44, 184, 3, 200, 52, 216, 14, 232, 60, 248, 64, 264, 68, 280, 18, 296, 76, 312, 5, 328, 84, 344, 22, 360, 92, 376, 384, 392, 100, 408, 26, 424, 108, 440, 7, 456, 116, 472, 30, 488, 124, 504, 32 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also column 8 of A059897.

A self-inverse permutation of the positive integers with no fixed points; A073675 composed with A120230.

The permutation swaps pairs of integers whose ratio is 1:8 or 1:2, these ratios corresponding to the factorizations 1*8 = 2*4 = 8.

LINKS

Peter Munn, Table of n, a(n) for n = 1..5120

Index entries for sequences that are permutations of the natural numbers

FORMULA

a(n) = A059897(8,n) = A059897(n,8).

a(n) = A073675(A120230(n)) = A120230(A073675(n)) = A073675(n) * A120230(n) / n.

PROG

(PARI) T(n, k) = {if (n==1, return (k)); if (k==1, return (n)); my(fn=factor(n), fk=factor(k)); vp = setunion(fn[, 1]~, fk[, 1]~); prod(i=1, #vp, vp[i]^(bitxor(valuation(n, vp[i]), valuation(k, vp[i])))); }

a(n) = T(n, 8); \\ Michel Marcus, Apr 23 2019

CROSSREFS

Cf. A059897, A073675, A120230, A307267.

Sequence in context: A248293 A151726 A070290 * A173855 A143368 A160415

Adjacent sequences:  A307263 A307264 A307265 * A307267 A307268 A307269

KEYWORD

nonn

AUTHOR

Peter Munn, Apr 01 2019

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 5 21:00 EDT 2020. Contains 335473 sequences. (Running on oeis4.)