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Meaning of happy number | Babel Free

Noun CEFR B2

Definitions

Any number that eventually reaches 1 after some number of iterations of replacing each of its digits by the sum of that digit's squares.

Equivalents

Suomi onnellinen luku

Examples

“13 is a happy number⟳ because 1² + 3² is 10, and 1² + 0² is 1.”

CEFR level

B2
Upper Intermediate
This word is part of the CEFR B2 vocabulary — upper intermediate level.
See all B2 English words →

See also

happy panda happy path happy pill happy place happy puppet syndrome happy sack

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