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A308221 Number of Egyptian fractions of denominator n which are sum of 3 unit fractions. 3
3, 6, 8, 11, 11, 16, 13, 19, 19, 22, 16, 29, 18, 26, 29, 31, 21, 38, 22, 41, 37, 32, 25, 51, 33, 36, 41, 49, 27, 58, 28, 51, 44, 42, 49, 69, 28, 45, 51, 71, 31, 74, 32, 61, 69, 48, 36, 87, 48, 67, 58, 68, 36, 82, 66, 85, 62, 54, 41, 109, 33, 57, 86, 82, 69, 89, 40, 80, 71, 98, 44, 121, 38, 59, 91, 84, 77, 101, 46, 118, 81, 62, 52, 139, 79, 65, 79, 106, 49, 138, 80, 89, 77, 70, 83, 143, 47, 98, 107, 128 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..100.

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

EXAMPLE

There are a(1) = 3 Egyptian fractions with denominator n = 1 which are sums of 3 unit fractions: 1/1 = 1/3 + 1/3 + 1/3, 2/1 = 1/1 + 1/2 + 1/2, and 3/1 = 1/1 + 1/1 + 1/1.

CROSSREFS

Cf. A308219, A308220, A308415

Sequence in context: A310135 A124051 A294086 * A277732 A026604 A013642

Adjacent sequences:  A308218 A308219 A308220 * A308222 A308223 A308224

KEYWORD

nonn

AUTHOR

Cyril Banderier, May 15 2019

STATUS

approved

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Last modified January 26 23:05 EST 2020. Contains 331289 sequences. (Running on oeis4.)