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A308415 Number of irreducible Egyptian fractions of denominator n which are the sum of 3 unit fractions. 3
3, 3, 5, 5, 8, 5, 10, 8, 11, 8, 13, 8, 15, 10, 13, 12, 18, 11, 19, 14, 19, 13, 22, 14, 22, 15, 22, 18, 24, 13, 25, 20, 23, 18, 28, 18, 25, 20, 28, 22, 28, 19, 29, 24, 29, 20, 33, 24, 35, 23, 32, 27, 33, 22, 42, 28, 35, 24, 38, 24, 30, 26, 38, 31 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..64.

Cyril Banderier, Florian Luca, Francesco Pappalardi, Numerators of Egyptian fractions, 2019.

EXAMPLE

There are a(2)=3 irreducible fractions with denominator n=2 which are the sums of 3 unit fractions: 1/2 = 1/8 + 1/8 + 1/4 and 3/2 = 1/2 + 1/2 + 1/2, and 5/2 = 1/1 + 1/1 + 1/2.

CROSSREFS

Cf. A308219, A308220, A308221.

Sequence in context: A247577 A282207 A046200 * A063281 A117772 A026924

Adjacent sequences:  A308412 A308413 A308414 * A308416 A308417 A308418

KEYWORD

nonn

AUTHOR

Cyril Banderier, May 25 2019

STATUS

approved

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Last modified October 25 00:01 EDT 2020. Contains 338010 sequences. (Running on oeis4.)