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A153076 Smallest number m such that sigma(m) = A002110(n) where A002110(n) is the product of the first n primes. 4
5, 29, 104, 1538, 13842, 188424, 3249576, 101864576, 2388809736, 59720243400, 2571228006912, 85266458294400, 6038197537693842, 227036227417289064, 12129959730964036050, 606111287080086323712, 36186481977293685109248 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Ray Chandler, Max Alekseyev, Table of n, a(n) for n = 2..24

Max A. Alekseyev, Computing the Inverses, their Power Sums, and Extrema for Euler's Totient and Other Multiplicative Functions. Journal of Integer Sequences, Vol. 19 (2016), Article 16.5.2

FORMULA

a(n) = A051444(A002110(n)). - Ray Chandler

EXAMPLE

a(9) = 101864576. Sigma(101864576) = A002110(9) = 223092870 = 2*3*5*7*11*13*17*19*23.

CROSSREFS

Cf. A000203, A002110, A153077, A153078.

Sequence in context: A139856 A097345 A097344 * A034700 A057721 A085151

Adjacent sequences:  A153073 A153074 A153075 * A153077 A153078 A153079

KEYWORD

nonn

AUTHOR

Donovan Johnson, Dec 19 2008

EXTENSIONS

Extended by Ray Chandler, Dec 28 2008

a(22)-a(24) added to b-file by Max Alekseyev, Jan 31 2012

STATUS

approved

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Last modified October 19 22:28 EDT 2018. Contains 316378 sequences. (Running on oeis4.)