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SequenceCases[list,patt]

gives a list of the sublists in list that match the sequence pattern patt.

SequenceCases[list,pattrhs]

gives a list of the values of rhs corresponding to sublists that match patt.

SequenceCases[list,patt,n]

includes only the first n matches.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Options  
Overlaps  
Properties & Relations  
See Also
Related Guides
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SequenceCases

SequenceCases[list,patt]

gives a list of the sublists in list that match the sequence pattern patt.

SequenceCases[list,pattrhs]

gives a list of the values of rhs corresponding to sublists that match patt.

SequenceCases[list,patt,n]

includes only the first n matches.

Details and Options

  • In SequenceCases[list,patt], patt can be an expression with head List that includes pattern constructs such as PatternSequence, Repeated (..), Blank (_), and BlankSequence (__).
  • The pattern patt can also be a pattern that matches a list but does not itself have head List.
  • With the default option setting OverlapsFalse, SequenceCases includes only sublists that do not overlap. With the setting OverlapsTrue, it includes sublists that overlap.
  • With Overlaps->All, multiple sublists that match the same pattern are all included. With Overlaps->True, only the first such matching sublist at a given position is included.

Examples

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Basic Examples  (2)

Find sublists that match a pattern:

Wolfram Language code: SequenceCases[{a, b, x, x, a, c}, {a, _}]

Perform a replacement on each match:

Wolfram Language code: SequenceCases[{a, b, x, x, a, c}, {a, x_} :> f[x]]

Count the length of all contiguous sequences of b:

Wolfram Language code: SequenceCases[{a, b, b, a, b, b, b}, {p : Repeated[b]} :> Length[{p}]]

Scope  (3)

Find sequences of elements that match a pattern:

Wolfram Language code: SequenceCases[Range[1000], {_ ? PrimeQ, _, _ ? PrimeQ}]

Find all overlapping sequences in a list:

Wolfram Language code: SequenceCases[Range[10], list_ /; Length[list] == 6, Overlaps -> True]

Evaluate a function on the cases found:

Wolfram Language code: SequenceCases[Range[1000], {a_ ? PrimeQ, b_, c_ ? PrimeQ} :> Row[Superscript@@@FactorInteger[b]]]

Options  (2)

Overlaps  (2)

Allow overlaps:

Wolfram Language code: SequenceCases[{a, b, a, b, a, b, a, b}, {a, b, a, b}, Overlaps -> True]

Allow no overlaps:

Wolfram Language code: SequenceCases[{a, b, a, b, a, b, a, b}, {a, b, a, b}, Overlaps -> False]

Allow overlaps starting at different positions:

Wolfram Language code: SequenceCases[{a, b, c, d}, {__}, Overlaps -> True]

Allow no overlaps:

Wolfram Language code: SequenceCases[{a, b, c, d}, {__}, Overlaps -> False]

Allow all overlaps:

Wolfram Language code: SequenceCases[{a, b, c, d}, {__}, Overlaps -> All]

Properties & Relations  (3)

Find the position of a sequence:

Wolfram Language code: SequencePosition[{a, b, 1, 2, c, d, 3, 4}, {__Symbol}, Overlaps -> False]

Find the actual sequence:

Wolfram Language code: SequenceCases[{a, b, 1, 2, c, d, 3, 4}, {__Symbol}, Overlaps -> False]

Count the number of cases:

Wolfram Language code: SequenceCount[{a, b, 1, 2, c, d, 3, 4}, {__Symbol}, Overlaps -> False]

Replace the sequence by an expression:

Wolfram Language code: SequenceReplace[{a, b, 1, 2, c, d, 3, 4}, {__Symbol} -> "X"]

For lists of characters, SequenceCases is similar to StringCases:

Wolfram Language code: text = "On 31/12/2003 we left, and on 5/3/2004 we came back";
Wolfram Language code: SequenceCases[Characters[text], {_ ? LetterQ..}]
Wolfram Language code: StringCases[text, LetterCharacter..]

SubsetCases matches the elements of the sequence in any order:

Wolfram Language code: SubsetCases[{1, a, 2, 3, a, b, c}, {a, _Integer}]

SequenceCases matches the sequence only in the specified order:

Wolfram Language code: SequenceCases[{1, a, 2, 3, a, b, c}, {a, _Integer}]
Wolfram Research (2015), SequenceCases, Wolfram Language function, https://reference.wolfram.com/language/ref/SequenceCases.html.

Text

Wolfram Research (2015), SequenceCases, Wolfram Language function, https://reference.wolfram.com/language/ref/SequenceCases.html.

CMS

Wolfram Language. 2015. "SequenceCases." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/SequenceCases.html.

APA

Wolfram Language. (2015). SequenceCases. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/SequenceCases.html

BibTeX

@misc{reference.wolfram_2026_sequencecases, author="Wolfram Research", title="{SequenceCases}", year="2015", howpublished="\url{https://reference.wolfram.com/language/ref/SequenceCases.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_sequencecases, organization={Wolfram Research}, title={SequenceCases}, year={2015}, url={https://reference.wolfram.com/language/ref/SequenceCases.html}, note=[Accessed: 13-June-2026]}