A374583 a(n) = number of Egyptian fractions 1 = 1/x_1 + ... + 1/x_n such that 0 < x_1 < ... < x_n and x_k | x_n for all k = 1..n.

1, 0, 1, 5, 44, 975, 59234, 15474226

Offset

1,4

Comments

Also, number of integers m such that m is the sum of n distinct divisors of m including 1.

x_n <= A000058(n-1)-1.

Links

Table of n, a(n) for n=1..8.

Crossrefs

Cf. A002967, A280518, A374582.

Sequence in context: A218375 A360988 A058792 * A113948 A215517 A215584

Adjacent sequences: A374580 A374581 A374582 * A374584 A374585 A374586

Keyword

nonn,more,hard

Author

Max Alekseyev, Jul 12 2024

Status

approved