null sequence

C1/C2 (Advanced)
UK/ˈnʌl ˈsiːkwəns/US/ˈnʌl ˈsiːkwəns/

Formal, Technical, Academic

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Definition

Meaning

A sequence (especially in mathematics) whose terms approach zero as the sequence progresses.

A sequence that converges to zero; also used metaphorically to describe a series of events or elements that diminish to nothingness or insignificance.

Linguistics

Semantic Notes

The term is almost exclusively used in technical contexts, particularly mathematics (analysis, calculus) and computer science. Its metaphorical use is rare and highly specialized.

Dialectal Variation

British vs American Usage

Differences

No significant difference in meaning. Spelling remains consistent.

Connotations

Identical technical meaning in both varieties.

Frequency

Equally rare outside technical fields in both regions.

Vocabulary

Collocations

strong
convergent null sequencedefine a null sequencelimit of a null sequence
medium
acts as a null sequenceexample of a null sequenceproperty of a null sequence
weak
strictly null sequenceabsolutely null sequenceessentially null sequence

Grammar

Valency Patterns

The sequence (a_n) is a null sequence.To prove that (x_n) is a null sequence.A null sequence of real numbers.

Vocabulary

Synonyms

Strong

zero-sequence (in specific contexts)

Neutral

sequence converging to zerovanishing sequence

Weak

diminishing seriestending-to-zero sequence

Vocabulary

Antonyms

divergent sequenceunbounded sequencesequence with a non-zero limit

Phrases

Idioms & Phrases

  • [No common idioms. Technical term.]

Usage

Context Usage

Business

Extremely rare, potentially in highly technical financial modelling.

Academic

Primary context. Used in mathematics, engineering, and theoretical computer science lectures and papers.

Everyday

Virtually never used.

Technical

Standard term in mathematical analysis, signal processing, and algorithm design.

Examples

By Part of Speech

verb

British English

  • [Not applicable as a verb]

American English

  • [Not applicable as a verb]

adverb

British English

  • [Not applicable as an adverb]

American English

  • [Not applicable as an adverb]

adjective

British English

  • The null-sequence property is fundamental to convergence tests.

American English

  • We need a null-sequence argument to complete the proof.

Examples

By CEFR Level

A2
  • [Too advanced for A2]
B1
  • [Too advanced for B1]
B2
  • In calculus, a null sequence gets closer and closer to zero.
C1
  • The lemma states that the product of a bounded sequence and a null sequence is itself a null sequence.
  • To demonstrate convergence, we first show that the tail of the series forms a null sequence.

Learning

Memory Aids

Mnemonic

Think of 'null' as zero and 'sequence' as a list. A 'null sequence' is a list of numbers that eventually gets as close to zero as you want.

Conceptual Metaphor

A JOURNEY TO NOTHINGNESS (The sequence travels towards the destination of zero).

Watch out

Common Pitfalls

Translation Traps (for Russian speakers)

  • Avoid direct translation as 'нулевая последовательность' in non-mathematical contexts, as it will sound bizarre. In English, it is not used metaphorically like 'ничтожный ряд событий' might be in Russian.

Common Mistakes

  • Using 'null sequence' to mean an empty sequence (a sequence with no terms). A null sequence has infinitely many terms that approach zero.
  • Using it in general language to mean 'a series of unimportant events'.

Practice

Quiz

Fill in the gap
For the series to converge, the terms must form a .
Multiple Choice

In which field is the term 'null sequence' primarily used?

FAQ

Frequently Asked Questions

No. An empty sequence has no terms. A null sequence has infinitely many terms, but their limit is zero.

Almost never. It is a technical term specific to mathematics and related disciplines.

For any arbitrarily small positive number, the absolute value of the terms eventually becomes and stays smaller than that number.

Conceptually related (both imply 'nothing'), but 'null sequence' is a precise mathematical term, while 'null and void' is a general legal idiom.