Self-organizing list

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Possible patterns of bracelets of length n
corresponding to the k-th integer partition
(set partitions up to rotation and reflection)
The 3 bracelets with 3 red and 3 green beads. The one in the middle is chiral, so there are 4 necklaces.
Compare box(6,9) in the triangle.
The 11 bracelets with 2 red, 2 yellow and 2 green beads. The leftmost one and the four rightmost ones are chiral, so there are 16 necklaces.
Compare box(6,7) in the triangle.
16 Tantrix tiles, corresponding to the 16 necklaces with 2 red, 2 yellow and 2 green beads.

In combinatorics, a k-ary necklace of length n is an equivalence class of n-character strings over an alphabet of size k, taking all rotations as equivalent. It represents a structure with n circularly connected beads of up to k different colors.

A k-ary bracelet, also referred to as a turnover (or free) necklace, is a necklace such that strings may also be equivalent under reflection. That is, given two strings, if each is the reverse of the other then they belong to the same equivalence class. For this reason, a necklace might also be called a fixed necklace to distinguish it from a turnover necklace.

Technically, one may classify a necklace as an orbit of the action of the cyclic group on n-character strings, and a bracelet as an orbit of the dihedral group's action.

Equivalence classes

Number of necklaces

There are

different k-ary necklaces of length n, where φ is the Euler's totient function.[1]

Number of bracelets

There are

different k-ary bracelets of length n, where Nk(n) is the number of k-ary necklaces of length n.

Examples

Necklace example

If there are n beads, all unique, on a necklace joined at the ends, then the number of unique orderings on the necklace, after allowing for rotations, is n!/n, for n > 0. This may also be expressed as (n − 1)!. This number is less than the general case, which lacks the requirement that each bead must be unique.

An intuitive justification for this can be given. If there is a line of n unique objects ("beads"), the number of combinations would be n!. If the ends are joined together, the number of combinations are divided by n, as it is possible to rotate the string of n beads into n positions.

Bracelet example

If there are n beads, all unique, on a bracelet joined at the ends, then the number of unique orderings on the bracelet, after allowing for rotations and reflection, is n!/(2n), for n > 2. Note that this number is less than the general case of Bn(n), which lacks the requirement that each bead must be unique.

To explain this, one may begin with the count for a necklace. This number can be further divided by 2, because it is also possible to flip the bracelet over.

Aperiodic necklaces

An aperiodic necklace of length n is an equivalence class of size n, i.e., no two distinct rotations of a necklace from such class are equal.

According to Moreau's necklace-counting function, there are

different k-ary aperiodic necklaces of length n, where μ is the Möbius function.

Each aperiodic necklace contains a single Lyndon word so that Lyndon words form representatives of aperiodic necklaces.

Products of Necklaces

The limit of products of the numbers of the fixed necklaces of length n composed of beads of types  ::

, ,

where the coefficient of in the expansion of the product

presents the number of permutations of n with k inversions, expressed by a Mahonian number: Before you resolve whether or not chrome steel cookware is value buying, lets first discuss what chrome steel cookware is. Chrome steel is made from an alloy, or a mixture of metals. Most commonly, fundamental iron with chromium, nickel or some other minor metals. The chromium gives rust safety and gives your cookware durability. The nickel supplies rust protection as effectively, and provides a polished look. Most properly made stainless steel cookware has copper or aluminum added to the underside of the pan or pot. That is done to increases the power of the pot or pan to conduct heat.
The perfect stainless-steel cookware is the primary category, however still it is divided into several subcategories based mostly on the standard and the price range. It may be complicated to choose the most effective stainless steel cookware out of the classes that can meet your necessities. That is where we took a step forward to explain you all the knowledge that might be useful for you to understand how to choose the most effective stainless-steel cookware. The very best stainless-steel cookware set is manufactured from low-cost to costly and quality constructed pots and pans.
You'll discover magnetic stainless-steel in the layer on the surface of some quality pieces of chrome steel. That is to make it compatible with induction stovetops, which contain using a quickly charging electromagnetic discipline to warmth cookware. Excessive-quality stainless-steel, like All-Clad , uses three layers of metallic—the austenite layer of steel on the inside, ferrite metal on the skin, and a layer of aluminum sandwiched between the 2 for optimal warmth conductivity (steel alone doesn't conduct warmth evenly). Lesser-high quality stainless steel is normally just one layer of austenitic chrome steel.
Aesthetically speaking, chrome steel is a sensible alternative should you want to display or hang pots or pans. The clear, crisp look of all stainless-steel kitchenware can transform a mishmash of cookware into a complicated décor statement. In case you adored this informative article as well as you wish to receive details relating to best stainless steel cookware i implore you to go to the page. Chrome steel kettles, such as the Cuisinart Tea Kettle will mix particular person kitchenware right into a cohesive and pleasant entity. Contemplate buying stainless steel utensils as nicely. Already acquired a stunning stainless-steel cookware assortment? The Cuisinart Chef’s Assortment stainless pot rack is perhaps the completion for a kitchen, releasing up house and making these pots and pans readily accessible. Get the stainless-steel cookware of your culinary dreams at Macy’s!
Hard-anodized aluminum cookware is one of the most popular forms of material, despite the fact that many individuals do not quite perceive the construction. Onerous-anodized aluminum is plain aluminum that has been processed in a series of chemical baths charged with an electrical current. The result is a cloth that has the same superior warmth conductivity as aluminum however is non-reactive with acidic meals, reminiscent of tomatoes, and twice as laborious as chrome steel. Two drawbacks to onerous-anodized cookware are that it is not dishwasher-safe and, as a result of it is not magnetic, it will not work with induction vary tops.
The enamel over steel approach creates a chunk that has the heat distribution of carbon metal and a non-reactive, low-stick floor. Such pots are a lot lighter than most different pots of comparable dimension, are cheaper to make than stainless steel pots, and don't have the rust and reactivity problems with forged iron or carbon steel. quotation needed Enamel over steel is right for large stockpots and for other massive pans used principally for water-primarily based cooking. Due to its light weight and easy cleanup, enamel over steel is also popular for cookware used while camping. Clad aluminium or copper edit
Unique specialty cookware pieces served a la carte to compliment any cookware set are constructed of a sturdy Stainless Steel with a brushed exterior finish. Designed with an affect bonded, aluminum disk encapsulated base which distributes warmth shortly and evenly to allow precise temperature management. Handles are riveted for sturdiness and efficiency. The New Specialty Cookware is appropriate for all vary sorts together with induction. In addition to the multi use operate, another unique function is bottom to high inside quantity markings in both quarts and metric measurement; and each piece comes with a tempered glass lid, oven protected to 350°F.
Whether you're a cooking fans, an expert chef or just cooking for your family you recognize the significance of getting a totally stocked kitchen. Not only do you want the appropriate components, however you additionally want the proper instruments to get the job performed. In any type of primary cooking training lesson, you'll study that chrome steel is your new greatest good friend with regards to kitchen cookware. What you will also be taught is that quality cooking gear does not normally come at a reduced worth. For that reason, it is important to take excellent care of your cookware! Listed below are some fundamentals for stainless steel care.
To fight the uneven heating drawback, most stainless-steel pans are laminations of aluminum or copper on the underside to unfold the warmth round, and stainless-steel contained in the pan to supply a cooking floor that's impervious to whatever you may put inside. In my experience, this chrome steel surface is still too sticky to fry on, and for those who ever burn it you get a everlasting trouble spot. But, sometimes a stainless steel cooking surface comes in handy when you can't use aluminum (see below) so I hold some around. Select something with a fairly thick aluminum layer on the bottom.
Effectively, unless you’re a metals expert and go examine the manufacturing unit the place the metal is made to see whether or not their manufacturing course of creates a pure austenite with out corrosive supplies shaped, you’re not going to know for certain whether or not the craftsmanship of your stainless is of the very best high quality. I feel your greatest bet is to simply purchase excessive-quality stainless steel from the beginning, from a model with a status for good quality. But, I think I've figured out a technique that you could determine if the stainless cookware you have already got is potentially reactive. (See Gaichenkov link)

See also

References

43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.

External links



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  • Info on necklaces, Lyndon words, De Bruijn sequences