extravagant number

An extravagant number or wasteful number $n$ is an integer with a base $b$ representation of $k$ digits for which the prime factorization uses more than $k$ digits (with repeated prime factors grouped with exponents and the digits of those exponents counted whenever greater than 1). The first few extravagant numbers in base 10 are 4, 6, 8, 9, 12, 18, 20, 22, 24, 26, 28, 30, 33, 34, 36, 38, 39, 40, 42, 44, 45, 46, 48, etc. (listed in A046760 of Sloane’s OEIS).

References

1 D. Darling, “Economical number” in The Universal Book of Mathematics: From Abracadabra To Zeno’s paradoxes. Hoboken, New Jersey: Wiley (2004)

单词	ExtravagantNumber
释义	extravagant number An extravagant number or wasteful number $n$ is an integer with a base $b$ representation of $k$ digits for which the prime factorization uses more than $k$ digits (with repeated prime factors grouped with exponents and the digits of those exponents counted whenever greater than 1). The first few extravagant numbers in base 10 are 4, 6, 8, 9, 12, 18, 20, 22, 24, 26, 28, 30, 33, 34, 36, 38, 39, 40, 42, 44, 45, 46, 48, etc. (listed in A046760 of Sloane’s OEIS). References 1 D. Darling, “Economical number” in The Universal Book of Mathematics: From Abracadabra To Zeno’s paradoxes. Hoboken, New Jersey: Wiley (2004)
随便看	projective plane ProjectivePlaneOfATernaryRing projective plane of a ternary ring ProjectiveResolution projective resolution ProjectiveSpace projective space ProjectiveSpecialLinearGroup projective special linear group ProjectiveVariety projective variety Projectivity projectivity ProjectPlanetMathOutlinesSeries Project: PlanetMath Outlines Series PromiseProblem promise problem PronormalSubgroup pronormal subgroup Proof proof ProofEquivalenceOfFormulationOfFoundation proof equivalence of formulation of foundation ProofForOneEquivalentStatementOfBaireCategoryTheorem proof for one equivalent statement of Baire category theorem