A308221 Number of Egyptian fractions of denominator n which are sum of 3 unit fractions.

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

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: A124051 A294086 A350159 * A350546 A375930 A277732

Adjacent sequences: A308218 A308219 A308220 * A308222 A308223 A308224

Keyword

nonn

Author

Cyril Banderier, May 15 2019

Status

approved